Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2015	Jan. 29, 2016	Jun. 30, 2015
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	FY
Trading Symbol	MD
Entity Registrant Name	MEDNAX, INC.
Entity Central Index Key	0000893949
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		93,800,921
Entity Public Float			$ 6,829,814,854

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 51,572	$ 47,928
Short-term investments	8,853	6,035
Accounts receivable, net	444,737	352,191
Prepaid expenses	9,639	7,036
Deferred income taxes		45,961
Other assets	12,968	7,901
Total current assets	527,769	467,052
Investments	63,288	64,082
Property and equipment, net	83,634	66,048
Goodwill	3,366,150	2,776,188
Intangible assets, net	424,219	198,136
Other assets	82,154	36,742
Total assets	4,547,214	3,608,248
Current liabilities:
Accounts payable and accrued expenses	395,807	380,658
Current portion of long-term debt and capital lease obligations	11,883	10,465
Income taxes payable	21,081	25,150
Total current liabilities	428,771	416,273
Line of credit	343,500	368,000
Long-term debt and capital lease obligations, net	919,320	190,308
Long-term professional liabilities	176,532	148,651
Deferred income taxes	188,956	160,487
Other liabilities	52,289	58,963
Total liabilities	$ 2,109,368	$ 1,342,682
Commitments and contingencies
Shareholders' equity:
Preferred stock; $.01 par value; 1,000 shares authorized; none issued
Common stock; $.01 par value; 200,000 shares authorized; 93,739 and 96,030 shares issued and outstanding, respectively	$ 937	$ 960
Additional paid-in capital	926,235	886,877
Retained earnings	1,510,356	1,376,782
Total MEDNAX, Inc. shareholders' equity	2,437,528	2,264,619
Noncontrolling interests	318	947
Total equity	2,437,846	2,265,566
Total liabilities and equity	$ 4,547,214	$ 3,608,248

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, issued	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	93,739,000	96,030,000
Common stock, shares outstanding	93,739,000	96,030,000

Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Net revenue	$ 741,740	$ 722,273	$ 676,588	$ 639,395	$ 650,525	$ 626,506	$ 595,544	$ 566,338	$ 2,779,996	$ 2,438,913	$ 2,154,012
Operating expenses:
Practice salaries and benefits	461,074	450,033	422,803	419,595	404,345	394,794	372,216	372,040	1,753,505	1,543,395	1,361,318
Practice supplies and other operating expenses	26,164	24,007	24,878	23,431	23,549	21,570	22,466	21,417	98,480	89,002	82,388
General and administrative expenses	85,393	80,185	72,401	67,936	67,641	60,643	60,829	58,414	305,915	247,527	218,209
Depreciation and amortization	18,149	16,918	15,549	13,612	13,903	11,356	10,361	10,370	64,228	45,990	39,966
Total operating expenses	590,780	571,143	535,631	524,574	509,438	488,363	465,872	462,241	2,222,128	1,925,914	1,701,881
Income from operations	150,960	151,130	140,957	114,821	141,087	138,143	129,672	104,097	557,868	512,999	452,131
Investment and other income	751	567	384	142	195	563	335	1,635	1,844	2,728	1,696
Interest expense	(8,493)	(6,201)	(5,149)	(3,267)	(3,313)	(2,019)	(2,188)	(1,371)	(23,110)	(8,891)	(5,415)
Equity in earnings of unconsolidated affiliate	777	784	745	821	905	725	150		3,127	1,780
Total non-operating expenses	(6,965)	(4,850)	(4,020)	(2,304)	(2,213)	(731)	(1,703)	264	(18,139)	(4,383)	(3,719)
Income before income taxes	143,995	146,280	136,937	112,517	138,874	137,412	127,969	104,361	539,729	508,616	448,412
Income tax provision	51,581	55,640	52,889	43,928	50,594	51,174	48,944	40,701	204,038	191,413	167,895
Net income	92,414	90,640	84,048	68,589	88,280	86,238	79,025	63,660	335,691	317,203	280,517
Net loss attributable to noncontrolling interests	288	141	82	118	118	(31)	(9)		629	78
Net income attributable to MEDNAX, Inc.	$ 92,702	$ 90,781	$ 84,130	$ 68,707	$ 88,398	$ 86,207	$ 79,016	$ 63,660	$ 336,320	$ 317,281	$ 280,517
Net income attributable to MEDNAX, Inc.:
Earnings per share, Basic	$ 1.00	$ 0.98	$ 0.91	$ 0.73	$ 0.90	$ 0.87	$ 0.80	$ 0.64	$ 3.61	$ 3.22	$ 2.83
Earnings per share, Diluted	$ 0.99	$ 0.97	$ 0.90	$ 0.72	$ 0.89	$ 0.86	$ 0.79	$ 0.63	$ 3.58	$ 3.18	$ 2.78
Weighted average common shares:
Basic	92,790	92,949	92,500	94,231	98,066	99,088	98,411	99,076	93,077	98,588	99,112
Diluted	93,536	93,646	93,495	95,325	99,129	100,145	99,866	100,696	93,960	99,887	100,969

Consolidated Statements of Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Noncontrolling Interests [Member]
Balance at Dec. 31, 2012	$ 2,035,368	$ 1,000	$ 787,580	$ 1,246,788
Balance, Shares at Dec. 31, 2012		100,038
Net income (loss)	280,517
Net income (loss)	280,517			280,517
Common stock issued under employee stock option and employee stock purchase plan	28,697	$ 14	28,683
Common stock issued under employee stock option and employee stock purchase plan, shares		1,331
Issuance of restricted stock and vesting of deferred stock		$ 9	(9)
Issuance of restricted stock and vesting of deferred stock, shares		922
Stock-based compensation expense	31,288		31,288
Forfeitures of restricted stock, shares		(28)
Repurchased common stock	(51,863)	$ (11)	(8,570)	(43,282)
Repurchased common stock, shares		(1,056)
Excess tax benefit related to employee stock incentive plans	18,981		18,981
Balance at Dec. 31, 2013	2,342,988	$ 1,012	857,953	1,484,023
Balance, Shares at Dec. 31, 2013		101,207
Contributions from noncontrolling interests	1,025				$ 1,025
Net income (loss)	317,203				(78)
Net income (loss)	317,281			317,281
Common stock issued under employee stock option and employee stock purchase plan	42,876	$ 13	42,863
Common stock issued under employee stock option and employee stock purchase plan, shares		1,412
Issuance of restricted stock and vesting of deferred stock		$ 6	(6)
Issuance of restricted stock and vesting of deferred stock, shares		573
Issuance of restricted stock for contingent consideration	705		705
Issuance of restricted stock for contingent consideration, shares		12
Stock-based compensation expense	31,719		31,719
Forfeitures of restricted stock, shares		(34)
Repurchased common stock	(488,429)	$ (71)	(63,836)	(424,522)
Repurchased common stock, shares		(7,140)
Excess tax benefit related to employee stock incentive plans	17,479		17,479
Balance at Dec. 31, 2014	2,265,566	$ 960	886,877	1,376,782	947
Balance, Shares at Dec. 31, 2014		96,030
Net income (loss)	335,691				(629)
Net income (loss)	336,320			336,320
Common stock issued under employee stock option and employee stock purchase plan	20,128	$ 5	20,123
Common stock issued under employee stock option and employee stock purchase plan, shares		463
Issuance of restricted stock and vesting of deferred stock		$ 5	(5)
Issuance of restricted stock and vesting of deferred stock, shares		527
Issuance of restricted stock for acquisition consideration	7,800	$ 1	7,799
Issuance of restricted stock for acquisition consideration, shares		114
Stock-based compensation expense	32,129		32,129
Forfeitures of restricted stock, shares		(30)
Repurchased common stock	$ (235,051)	$ (34)	(32,271)	(202,746)
Repurchased common stock, shares	(3,400)	(3,365)
Excess tax benefit related to employee stock incentive plans	$ 11,583		11,583
Balance at Dec. 31, 2015	$ 2,437,846	$ 937	$ 926,235	$ 1,510,356	$ 318
Balance, Shares at Dec. 31, 2015		93,739

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net income	$ 335,691	$ 317,203	$ 280,517
Adjustments to reconcile net income to net cash provided from operating activities:
Depreciation and amortization	64,228	45,990	39,966
Net change in fair value of contingent consideration liabilities	13	(417)	3,656
Stock-based compensation expense	32,129	31,719	31,288
Equity in earnings of unconsolidated affiliate	(3,127)	(1,780)
Distribution of earnings from unconsolidated affiliate	2,062
Deferred income taxes	14,494	2,559	15,920
Changes in assets and liabilities:
Accounts receivable	(55,391)	(57,018)	(37,331)
Prepaid expenses and other assets	(4,905)	1,506	212
Other assets	1,639	2,137	(3,541)
Accounts payable and accrued expenses	(7,874)	66,039	49,239
Income taxes payable	(4,101)	6,998	5,772
Payments of contingent consideration liabilities	(1,439)	(4,071)	(1,308)
Long-term professional liabilities	(2,064)	9,284	19,797
Other liabilities	(2,654)	2,492	1,211
Net cash provided from operating activities	368,701	422,641	405,398
Cash flows from investing activities:
Acquisition payments, net of cash acquired	(818,903)	(479,394)	(238,045)
Purchases of investments	(33,980)	(26,884)	(20,802)
Proceeds from maturities of investments	31,956	20,735	11,011
Purchases of property and equipment	(27,073)	(18,061)	(15,654)
Net cash used in investing activities	(848,000)	(503,604)	(263,490)
Cash flows from financing activities:
Borrowings on credit facility	2,121,500	1,754,500	911,500
Payments on credit facility	(2,156,000)	(1,213,500)	(1,028,500)
Proceeds from issuance of senior notes	750,000
Payments for financing costs	(14,190)	(4,281)
Payments of contingent consideration liabilities	(12,856)	(11,740)	(10,365)
Payments on capital lease obligations	(2,171)	(159)	(99)
Excess tax benefit from exercises of stock options and vesting of restricted and deferred stock	11,583	17,462	18,579
Proceeds from issuance of common stock	20,128	42,876	28,697
Contribution from noncontrolling interests		1,025
Repurchases of common stock	(235,051)	(488,429)	(51,863)
Net cash provided from (used in) financing activities	482,943	97,754	(132,051)
Net increase in cash and cash equivalents	3,644	16,791	9,857
Cash and cash equivalents at beginning of year	47,928	31,137	21,280
Cash and cash equivalents at end of year	51,572	47,928	31,137
Supplemental disclosure of cash flow information:
Interest	20,367	7,323	3,312
Income taxes	181,005	161,841	$ 126,411
Non-cash investing and financing activities:
Value of common stock issued for an acquisition	7,800
Equipment financed through capital leases	3,135	$ 1,244
Property and equipment included in accounts payable	$ 1,800

General	12 Months Ended
General	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
General	1. General: The principal business activity of MEDNAX, Inc. (“MEDNAX” or the “Company”) and its subsidiaries is to provide neonatal, anesthesia, maternal-fetal and other pediatric subspecialties physician services. The Company has contracts with affiliated business corporations or professional associations, limited liability companies and partnerships (“affiliated professional contractors”), which are separate legal entities that provide physician services in certain states and Puerto Rico. The Company and its affiliated professional contractors also have contracts with hospitals and other healthcare facilities to provide physician services, which include (i) fee-for-service contracts, whereby hospitals agree, in exchange for the Company’s services, to authorize the Company and its healthcare professionals to bill and collect the charges for medical services rendered by the Company’s affiliated healthcare professionals, and (ii) administrative fee contracts, whereby the Company is assured a minimum revenue level. In addition to the Company’s national physician network, during 2015 the Company acquired a radiology physician services and telemedicine company that provides outsourced radiology and telemedicine services to hospital, health system and radiology group facilities as well as a third-party receivables company that specializes in revenue recovery on accounts that require heightened expertise, labor and capital. During 2014, the Company acquired two complementary businesses that offer services to medical providers, including its own, consisting of a revenue cycle management company and a consulting services company.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2015

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies:

Principles of Presentation

The financial statements include all the accounts of the Company and its subsidiaries combined with the accounts of the affiliated professional contractors with which the Company currently has specific management arrangements. The Company’s agreements with affiliated professional contractors provide that the term of the arrangements are in most cases permanent, subject only to termination by the Company, except in the case of gross negligence, fraud or bankruptcy of the Company. The Company has the right to receive income, both as ongoing fees and as proceeds from the sale of its interest in the Company’s affiliated professional contractors, in an amount that fluctuates based on the performance of the affiliated professional contractors and the change in the fair value of the Company’s interest in the affiliated professional contractors. The Company has exclusive responsibility for the provision of all non-medical services required for the day-to-day operation and management of the Company’s affiliated professional contractors and establishes the guidelines for the employment and compensation of the physicians. In addition, the agreements provide that the Company has the right, but not the obligation, to purchase, or to designate a person(s) to purchase, the stock of the Company’s affiliated professional contractors for a nominal amount. Separately, in its sole discretion, the Company has the right to assign its interest in the agreements. Based upon the provisions of these agreements, the Company has determined that the affiliated professional contractors are variable interest entities and that the Company is the primary beneficiary as defined in the accounting guidance for consolidation. All significant intercompany and interaffiliate accounts and transactions have been eliminated.

On June 1, 2014, the Company entered into a joint venture in which it owns a 75% economic interest. The Company has a management agreement with the joint venture and, based on the terms of the agreement, the Company has determined that the joint venture is a variable interest entity for which the Company is the primary beneficiary as defined in the accounting guidance for consolidation. Accordingly, the financial results of the joint venture are fully consolidated into the Company’s operating results. The equity interests of the outside investor in the equity and results of operations of this consolidated entity are accounted for and presented as noncontrolling interests. Also on June 1, 2014, the Company entered into a second joint venture in which it owns a 37.5% economic interest. The Company accounts for this joint venture under the equity method of accounting because the Company exercises significant influence over, but does not control, this entity.

Prior period financial statements have been adjusted to conform with the current year presentation for the presentation of intangible assets and other current assets as well as for changes resulting from the adoption of the accounting guidance related to the presentation of debt issuance costs.

For the presentation of debt issuance costs, the Company reclassified its debt issuance costs, other than those related to its revolving line of credit, as a direct deduction from the related long-term debt. This reclassification was recorded as a change in accounting principle. See “New Accounting Pronouncements.” The impact of the adjustments made to prior period balance sheet is presented below (in thousands):


	December 31, 2014
	Previously Reported		Adjustment			As Revised
*Consolidated Balance Sheet:*
Other assets (noncurrent portion) (1)	$	235,425	$	(547	)	$	234,878
Total assets	$	3,608,795	$	(547	)	$	3,608,248
Long-term debt and capital lease obligations	$	190,855	$	(547	)	$	190,308
Total liabilities	$	1,343,229	$	(547	)	$	1,342,682

(1)	For the year ended December 31, 2014, the previously reported amount of other noncurrent assets included intangible assets, net of accumulated amortization and other noncurrent assets. For the year ended December 31, 2015, intangible assets and other noncurrent assets are separately presented.

Recently Adopted Accounting Pronouncements

In November 2015, the accounting guidance related to deferred income tax assets and liabilities was amended to require that such amounts be presented in the balance sheet as noncurrent rather than separating deferred income tax assets and liabilities into current and noncurrent amounts. This guidance is required to be adopted on January 1, 2017 and may be applied either prospectively to all deferred tax assets and liabilities as of year-end 2015 or retrospectively to all periods presented. As permitted, the Company adopted this guidance prospectively as of December 31, 2015 as a change in accounting principle.

In March 2015, the accounting guidance related to the presentation of debt issuance costs was amended to require that such costs be presented in the balance sheet as a direct deduction from the carrying amount of the related debt liability but does not change the recognition and measurement requirements for debt issuance costs. In June 2015, it was clarified that debt issuance costs related to revolving lines of credit were excluded from this guidance and that a company would be responsible for adopting an accounting policy for the presentation of such costs, including treating such costs as an amortizable asset. This guidance is required to be adopted on January 1, 2016 retrospectively to all periods presented. As permitted, the Company adopted this guidance as of December 31, 2015 as a change in accounting principle and applied retrospectively to all periods presented. The Company will continue to present debt issuance costs related to its revolving line of credit as an amortizable asset.

New Accounting Pronouncements

In September 2015, the accounting guidance related to business combinations was amended to require that adjustments to provisional amounts that are identified during the measurement period be recognized in the reporting period in which the adjustment amounts are determined rather than being retrospectively recognized as of the acquisition date. Such amounts will be required to either be presented separately on the face of the income statement or within a footnote disclosure stating what the impacts on prior period financial statements would have been had such amounts had been recognized as of the acquisition date. This guidance will become effective for the Company on January 1, 2016, with early adoption permitted. The adoption of this guidance is not expected to have a material impact on the Company’s Consolidated Financial Statements.

In February 2015, the accounting guidance related to consolidation was amended to include changes to both the variable and voting interest models used by companies to evaluate whether an entity should be consolidated. This guidance will become effective for the Company on January 1, 2016, and early adoption is permitted. The adoption of this guidance is not expected to have an impact on the Company’s Consolidated Financial Statements.

In May 2014, the accounting guidance related to revenue recognition was amended to outline a single, comprehensive model for accounting for revenue from contracts with customers. While this guidance supersedes existing revenue recognition guidance, it closely aligns with current accounting principles generally accepted in the United States (“GAAP”). The new guidance will become effective for the Company on January 1, 2018, with early adoption permitted on January 1, 2017. The Company is currently evaluating the impact, if any, the adoption of this guidance will have on the Company’s Consolidated Financial Statements.

Accounting Estimates and Assumptions

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and assumptions are involved in the calculation of the Company’s allowance for contractual adjustments and uncollectibles on accounts receivable, liabilities for self-insured amounts and claims incurred but not reported related to the Company’s professional liability risks, the fair value of goodwill, and liabilities for uncertain tax positions. Actual results could differ from those estimates.

Segment Reporting

The results of the Company’s operations are aggregated into a single reportable segment for purposes of presenting financial information in accordance with the accounting guidance for segment reporting.

The following table summarizes the Company’s net revenue by service line (in percentages):


	Years Ended December 31,
	2015			2014			2013
Neonatal and other pediatric subspecialties		44	%		50	%		52	%
Anesthesia		37	%		36	%		32	%
Maternal-fetal		9	%		9	%		11	%
Pediatric cardiology		4	%		4	%		5	%
Radiology		4	%		—			—
Other services		2	%		1	%		—

		100	%		100	%		100	%

Revenue Recognition

Patient service revenue is recognized at the time services are provided by the Company’s affiliated physicians. Almost all of the Company’s patient service revenue is reimbursed by government-sponsored healthcare programs and third-party insurance payors. Payments for services rendered to the Company’s patients are generally less than billed charges. The Company monitors its revenue and receivables from these sources and records an estimated contractual allowance to properly account for the anticipated differences between billed and reimbursed amounts.

Accordingly, patient service revenue is presented net of an estimated provision for contractual adjustments and uncollectibles. The Company estimates allowances for contractual adjustments and uncollectibles on accounts receivable based upon historical experience and other factors, including days sales outstanding (“DSO”) for accounts receivable, evaluation of expected adjustments and delinquency rates, past adjustments and collection experience in relation to amounts billed, an aging of accounts receivable, current contract and reimbursement terms, changes in payor mix and other relevant information. Contractual adjustments result from the difference between the physician rates for services performed and the reimbursements by government-sponsored healthcare programs and insurance companies for such services.

In addition, the Company generates revenue for services rendered under various coding and billing contracts. Contract terms are specific to each customer and may include a combination of a flat fee for coding of medical charts, a fixed fee per patient visit as well as a percentage of cash collections received by the providers. Revenue for flat and fixed fee arrangements is recognized in the month the coding occurs or the patient visit occurs. Revenue for percentage fees are recognized in the month that cash is collected for customers from payors. Revenue recorded for these services during 2015 were immaterial.

Accounts receivable are primarily amounts due under fee-for-service contracts from third-party payors, such as insurance companies, self-insured employers and patients and government-sponsored healthcare programs geographically dispersed throughout the United States and its territories. Concentration of credit risk relating to accounts receivable is limited by the number, diversity and geographic dispersion of the business units managed by the Company, as well as by the large number of patients and payors, including the various governmental agencies in the states in which the Company provides services. Receivables from government agencies made up approximately 19% of net accounts receivable at December 31, 2015 and 2014.

Cash and Cash Equivalents

Cash equivalents are defined as all highly liquid financial instruments with maturities of 90 days or less from the date of purchase. The Company’s cash equivalents typically consist of demand deposits, amounts on deposit in money market accounts, and funds invested in overnight repurchase agreements. Cash equivalent balances may, at certain times, exceed federally insured limits.

Certain cash equivalents carried by the Company are subject to the fair value provisions of the accounting guidance for fair value measurements. See “Fair Value Measurements” below.

Investments

Investments consist of municipal debt securities, federal home loan securities and certificates of deposit. Investments with remaining maturities of less than one year are classified as short-term investments. Investments classified as long-term have maturities of one year to six years.

The Company intends and has the ability to hold its held-to-maturity securities to maturity, and therefore carries such investments at amortized cost in accordance with the provisions of the accounting guidance for investments in debt and equity securities.

Property and Equipment

Property and equipment are recorded at original purchase cost. Depreciation of property and equipment is computed using the straight-line method over the estimated useful lives of the underlying assets. Estimated useful lives are generally 20 years for buildings; three to 10 years for medical equipment, computer equipment, software and furniture; and the lesser of the useful life or the remaining lease term for leasehold improvements and capital leases. Upon sale or retirement of property and equipment, the related cost and accumulated depreciation are eliminated from the respective accounts and any resulting gain or loss is included in earnings.

Business Acquisitions

The Company accounts for business acquisitions as required by the provisions of the accounting guidance for business combinations such that all business combinations are required to be accounted for at fair value. The guidance requires the Company to expense certain acquisition costs as they are incurred. In accordance with the acquisition method of accounting, any identifiable assets acquired and any liabilities assumed are recognized and measured at their fair values on the acquisition date. If information about facts and circumstances existing as of the acquisition date is incomplete at the end of the reporting period in which a business acquisition occurs, the Company will report provisional amounts for the items for which the accounting is incomplete. The measurement period ends once the Company receives sufficient information to finalize the fair values; however, the period will not exceed one year from the acquisition date. Any material adjustments recognized during the measurement period are to be reflected retrospectively in the Consolidated Financial Statements of the subsequent period; however, beginning on January 1, 2016 any adjustments to provisional amounts that are identified during the measurement period will be recognized in the reporting period in which the adjustment amounts are determined.

In connection with certain acquisitions, the Company enters into agreements to pay additional amounts in cash or common stock based on the achievement of certain performance measures for up to five years ending after the acquisition dates. The Company measures this contingent consideration at fair value at the acquisition date and records such contingent consideration as a liability or equity on the Company’s Consolidated Balance Sheets on the acquisition date. The fair value of each contingent consideration liability is remeasured at each reporting period with any change in fair value recognized as income or expense within operations in the Company’s Consolidated Statements of Income. See Note 6 for more information on the Company’s business acquisitions.

Goodwill and Other Intangible Assets

The Company records acquired assets and liabilities at their respective fair values under the acquisition method of accounting. Goodwill represents the excess of cost over the fair value of the net assets acquired. Intangible assets with finite lives, principally physician and hospital agreements, customer relationships, patented technology and trade names, are recognized apart from goodwill at the time of acquisition based on the contractual-legal and separability criteria established in the accounting guidance for business combinations. Intangible assets with finite lives are amortized on either an accelerated basis based on the annual undiscounted economic cash flows associated with the particular intangible asset or on a straight-line basis over their estimated useful lives. Intangible assets with finite lives are amortized over periods of one to 20 years.

Goodwill is tested for impairment at a reporting unit level on at least an annual basis in accordance with the subsequent measurement provisions of the accounting guidance for goodwill. The Company defines a reporting unit based upon its management structure for services provided in specific regions of the United States. The testing for impairment is completed using a two-step test. The first step compares the fair value of a reporting unit with its carrying amount, including goodwill. If the carrying amount of a reporting unit exceeds its fair value, a second step is performed to determine the amount of any impairment loss. The Company uses income and market-based valuation approaches to determine the fair value of its reporting units. These approaches focus on discounted cash flows and market multiples based on the Company’s market capitalization to derive the fair value of a reporting unit. The Company also considers the economic outlook for the healthcare services industry and various other factors during the testing process, including hospital and physician contract changes, local market developments, changes in third-party payor payments, and other publicly available information. The Company completed annual impairment tests in the third quarter of each of 2015, 2014 and 2013 and determined that goodwill was not impaired in any of the three years.

Long-Lived Assets

The Company is required to evaluate long-lived assets, including intangible assets subject to amortization, whenever events or changes in circumstances indicate that the carrying value of the assets may not be fully recoverable. The recoverability of such assets is measured by a comparison of the carrying value of the assets to the future undiscounted cash flows before interest charges to be generated by the assets. If long-lived assets are impaired, the impairment to be recognized is measured as the excess of the carrying value over the fair value. Long-lived assets held for disposal are reported at the lower of the carrying value or fair value less disposal costs. The Company does not believe there are any indicators that would require an adjustment to such assets or their estimated periods of recovery at December 31, 2015 pursuant to current accounting standards.

Common Stock Repurchases

The Company repurchases shares of its common stock as authorized from time to time by its Board of Directors. The Company treats repurchased shares of its common stock as authorized but unissued shares. The reacquisition cost of repurchased shares is recorded as a reduction in the respective components of shareholders’ equity.

Professional Liability Coverage

The Company maintains professional liability insurance policies with third-party insurers generally on a claims-made basis, subject to self-insured retention, exclusions and other restrictions. The Company’s self-insured retention under its professional liability insurance program is maintained primarily through a wholly owned captive insurance subsidiary. The Company records an estimate of liabilities for self-insured amounts and claims incurred but not reported based on an actuarial valuation using historical loss information, claim emergence patterns and various actuarial assumptions. Liabilities for claims incurred but not reported are not discounted.

Income Taxes

The Company records deferred income taxes using the liability method, whereby deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse.

The accounting guidance for uncertain tax positions prescribes a recognition threshold and measurement attribute for financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. The guidance also requires policy disclosures regarding penalties and interest and extensive disclosures regarding increases and decreases in uncertain tax positions as a result of tax positions taken in a current or prior period, settlements with taxing authorities and any lapse of an applicable statute of limitations. Additional qualitative discussion is required for any tax position that may result in a significant increase or decrease in uncertain tax positions within a 12-month period from the Company’s reporting date.

Stock Incentive Plans

The Company grants stock-based awards consisting primarily of restricted stock to key employees under its Amended and Restated 2008 Incentive Compensation Plan. In accordance with the accounting guidance for stock-based compensation, the Company measures the cost of employee services received in exchange for stock-based awards based on grant-date fair value and allocates the resulting compensation expense over the corresponding requisite service period using the graded vesting attribution method. The Company also performs analyses to estimate forfeitures of stock-based awards as required by the accounting guidance for stock-based compensation. The Company is required to assess its forfeiture estimates on at least an annual basis and adjust the estimates as necessary based on the number of awards that ultimately vest.

Net Income Per Common Share

Basic net income per common share is calculated by dividing net income by the weighted average number of common shares outstanding during the period. Diluted net income per common share is calculated by dividing net income by the weighted average number of common and potential common shares outstanding during the period. Potential common shares consist of outstanding restricted stock and stock options calculated using the treasury stock method. Under the treasury stock method, the Company includes the assumed excess tax benefits related to the potential exercise or vesting of its stock-based awards using the difference between the average market price for the applicable period less the option price, if any, and the fair value of the stock-based award on the date of grant multiplied by the applicable tax rate.

Fair Value Measurements

In accordance with the accounting guidance for fair value measurements and disclosures, the Company carries its money market funds included in cash and cash equivalents at fair value. In accordance with the three-tier fair value hierarchy under this guidance, the Company determined the fair value using quoted market prices, a Level 1 input as defined under the accounting guidance for fair value measurements. At December 31, 2015 and 2014, the Company’s money market funds had a carrying amount of $13.9 million and $5.1 million, respectively.

The Company also carries the cash surrender value of life insurance related to its deferred compensation arrangements at fair value. The investments underlying the life insurance contracts consist primarily of exchange-traded equity securities and mutual funds with quoted prices in active markets. In accordance with the three-tier fair value hierarchy, the Company determined the fair value using the cash surrender value of the life insurance, a Level 2 input as defined under the accounting guidance for fair value measurements. At December 31, 2015 and 2014, the Company’s cash surrender value of life insurance had a carrying amount of $14.5 million and $16.0 million, respectively.

In addition, the Company carries its contingent consideration liabilities related to acquisitions at fair value. In accordance with the three-tier fair value hierarchy, the Company determined the fair value of its contingent consideration liabilities using the income approach with assumed discount rates and payment probabilities. The income approach uses Level 3, or unobservable inputs as defined under the accounting guidance for fair value measurements. At December 31, 2015 and 2014, the Company’s contingent consideration liabilities had a fair value of $24.9 million and $35.3 million, respectively. See Note 6 for more information regarding the Company’s contingent consideration liabilities.

The carrying amounts of cash equivalents, short-term investments, accounts receivable and accounts payable and accrued expenses approximate fair value due to the short maturities of the respective instruments. The carrying values of long-term investments, line of credit, long-term debt and capital lease obligations approximate fair value. If the Company’s investments were measured at fair value, they would be categorized as Level 2 in the fair value hierarchy. If the Company’s line of credit and long-term debt were measured at fair value, they would be categorized as Level 2 in the fair value hierarchy.

Investments

12 Months Ended

Dec. 31, 2015

Investments, Debt and Equity Securities [Abstract]

Investments

3. Investments:

Investments held are summarized as follows (in thousands):


	December 31, 2015				December 31, 2014
	Short-Term		Long-Term		Short-Term		Long-Term
Municipal debt securities	$	8,608	$	34,858	$	5,539	$	35,827
Federal home loan securities		—		26,715		—		27,030
Certificates of deposit		245		1,715		496		1,225

	$	8,853	$	63,288	$	6,035	$	64,082

Contractual maturities of long-term investments are summarized as follows (in thousands):


	December 31,
	2015		2014
Due after one year through five years	$	60,383	$	54,959
Due after five years through six years		2,905		9,123

	$	63,288	$	64,082

- Definition

The entire disclosure for investments in certain debt and equity securities.

+ References + Details

Accounts Receivable and Net Revenue

12 Months Ended

Dec. 31, 2015

Receivables [Abstract]

Accounts Receivable and Net Revenue

4. Accounts Receivable and Net Revenue:

Accounts receivable, net consists of the following (in thousands):


	December 31,
	2015			2014
Gross accounts receivable	$	1,574,038		$	1,200,958
Allowance for contractual adjustments and uncollectibles		(1,129,301	)		(848,767	)

	$	444,737		$	352,191

Net revenue consists of the following (in thousands):


	Years Ended December 31,
	2015			2014			2013
Gross revenue	$	8,942,957		$	7,662,556		$	6,702,484
Contractual adjustments and uncollectibles		(6,389,195	)		(5,403,437	)		(4,695,232	)
Hospital contract administrative fees		226,234			179,794			146,760

	$	2,779,996		$	2,438,913		$	2,154,012

Accounts receivable of $444.7 million and $352.2 million at December 31, 2015 and 2014, respectively, consist primarily of amounts due from government-sponsored healthcare programs and third-party insurance payors for services provided by the Company’s affiliated physicians.

Net revenue of $2.8 billion, $2.4 billion and $2.2 billion for the years ended December 31, 2015, 2014 and 2013, respectively, consists primarily of gross billed charges for services provided by the Company’s affiliated physicians less an estimated allowance for contractual adjustments and uncollectibles to properly account for the anticipated differences between gross billed charge amounts and expected reimbursement amounts.

The Company’s contractual adjustments and uncollectibles as a percentage of gross patient service revenue vary slightly each year depending on several factors, including improved managed care contracting, changes in reimbursement from state Medicaid programs and other government-sponsored programs, shifts in the percentage of patient services being reimbursed under government-sponsored programs and annual price increases.

The Company’s annual price increases typically increase contractual adjustments as a percentage of gross patient service revenue. This increase is primarily due to Medicaid, Medicare and other government-sponsored healthcare programs that generally provide for reimbursements on a fee-schedule basis rather than on a gross charge basis. When the Company bills these programs, like other payors, on a gross-charge basis, it also increases its provision for contractual adjustments and uncollectibles by the amount of any price increase, resulting in a higher contractual adjustment percentage.

Property and Equipment

12 Months Ended

Dec. 31, 2015

Property, Plant and Equipment [Abstract]

Property and Equipment

5. Property and Equipment:

Property and equipment consists of the following (in thousands):


	December 31,
	2015			2014
Building	$	26,382		$	22,981
Land		6,683			6,683
Equipment and other		169,903			133,279

		202,968			162,943
Accumulated depreciation		(119,334	)		(96,895	)

	$	83,634		$	66,048

At December 31, 2015 and 2014, property and equipment includes medical and other equipment held under capital leases of approximately $5.4 million and $2.4 million, and related accumulated depreciation of approximately $2.3 million and $1.4 million, respectively. The Company recorded depreciation expense of approximately $22.2 million, $15.9 million and $15.5 million for the years ended December 31, 2015, 2014 and 2013, respectively.

Business Acquisitions

12 Months Ended

Dec. 31, 2015

Business Combinations [Abstract]

Business Acquisitions

6. Business Acquisitions:

During the year ended December 31, 2015, the Company completed 12 acquisitions, of which 10 were physician group practices including seven anesthesiology practices, two neonatology practices and one other pediatric subspecialty practice, and two non-practice acquisitions including a leading radiology physician services and telemedicine company and a complementary third-party receivables company. The acquisition-date fair value of the total consideration for the 12 acquisitions was $853.3 million, inclusive of cash acquired. Approximately $818.3 million was paid in cash, net of $23.0 million in cash acquired, $7.8 million was paid by issuing 114,306 shares of the Company’s common stock, $3.8 million was recorded as a contingent consideration liability and $0.4 million was recorded within other current liabilities.

The physician practice acquisitions expand the Company’s national network of physician practices. The Company expects to improve the results of these physician practices through improved managed care contracting, improved collections, identification of growth initiatives, as well as, operating and cost savings based on the significant infrastructure it has developed. The acquisition of the radiology physician services and telemedicine company provides a platform for growth in the radiology market as well as in the broader telemedicine market, and will further expand the Company’s service offerings to its hospital and health system partners. The acquisition of the third-party receivables company was an addition to our existing revenue cycle management company and is expected to further enhance the Company’s services offerings for its hospital and health system partners as an outsourced services capability.

The Company’s allocation of purchase price is as follows (in thousands):


	Radiology Acquisition			Other Acquisitions			Total
Current assets	$	51,736		$	11,445		$	63,181
Property and equipment		11,398			449			11,847
Other noncurrent assets		8,237			2,552			10,789
Goodwill		313,340			275,984			589,324
Other intangible assets		199,960			73,477			273,437
Current liabilities		(27,008	)		(1,160	)		(28,168	)
Deferred income tax liabilities—long-term		(15,850	)		(14,356	)		(30,206	)
Other long-term liabilities		(34,275	)		(2,618	)		(36,893	)

	$	507,538		$	345,773		$	853,311

One of the acquisitions completed during the year ended December 31, 2015 remains subject to a working capital adjustment.

The 114,306 shares of the Company’s common stock issued as a component of the purchase consideration for an acquisition completed during the year ended December 31, 2015 had an acquisition-date fair value of $7.8 million. The fair value of such shares was determined using the closing price on the New York Stock Exchange of the Company’s common stock less a discount for lack of marketability, reflecting a three year contractual restriction on disposition or assignment of such common stock.

The contingent consideration of $3.8 million recorded during the year ended December 31, 2015 is related to an agreement to pay an additional cash amount based on the achievement of certain performance measures for up to two years after the acquisition date. The accrued contingent consideration was recorded as a liability at acquisition-date fair value using the income approach with assumed discount rates ranging from 2.8% to 3.5% over the applicable terms and an assumed payment probability of 100% for each of the applicable years. The range of the undiscounted amount the Company could pay under the contingent consideration agreement is between $0 and $4.0 million. In addition, during the year ended December 31, 2015, the Company recorded a decrease to its contingent consideration liability of $1.0 million related to the change in fair value of certain contingent consideration agreements for which the performance measures will not be met. This change in fair value was recorded within operating income.

In addition, during the year ended December 31, 2015, the Company paid $14.3 million for contingent consideration related to certain prior-period acquisitions, of which all but the accretion recorded during 2015 was accrued as of December 31, 2014. In connection with prior-period acquisitions, the Company also recorded a net increase of $0.6 million to goodwill composed of a decrease in intangible assets of $5.3 million, an increase of $2.6 million in other current assets, a decrease of $2.6 million in other long-term liabilities and $0.6 million in additional cash consideration related to a working capital true-up adjustment and other measurement period adjustments. These adjustments did not have a material impact on the Company’s Consolidated Financial Statements in any period; therefore, the Company has not retrospectively adjusted such statements.

During 2014, the Company completed 13 acquisitions, composed of 11 physician group practices, a complementary revenue cycle management company as well as a consulting services company for total consideration of $488.6 million, consisting of $479.4 million in cash and $9.2 million of contingent consideration.

In June 2014, the Company entered into two joint ventures, one in which it owns a 75% economic interest and one in which it owns a 37.5% economic interest. The financial results of the 75% owned joint venture are fully consolidated into the Company’s operating results and are not material to the Consolidated Financial Statements. In connection with the 37.5% owned joint venture, the Company completed a nonmonetary exchange of certain operations with a fair value of $7.7 million as contribution to the joint venture. The carrying value of the goodwill transferred of $7.2 million and the fixed assets transferred of $0.5 million approximated the fair value of the contribution to this joint venture, and accordingly no gain or loss was recognized on the transaction. The investment in this joint venture is included in other assets, noncurrent, as presented in the Company’s Consolidated Balance Sheets.

The results of operations of the practices acquired in 2015 and 2014 have been included in the Company’s Consolidated Financial Statements from the dates of acquisition. The following unaudited pro forma information combines the consolidated results of operations of the Company on a GAAP basis and the acquisitions completed during 2015 and 2014, including adjustments for pro forma amortization and interest expense, as if the transactions had occurred on January 1, 2014 and January 1, 2013, respectively (in thousands, except per share data):


	Years Ended December 31,
	2015		2014
Net revenue	$	2,946,467	$	2,945,493
Net income		343,575		345,517
Net income per common share (1):
Basic	$	3.69	$	3.50
Diluted	$	3.66	$	3.46
Weighted average common shares (1):
Basic		93,077		98,588
Diluted		93,960		99,887

(1)	The comparison of net income per common share is affected by the changes in the number of weighted average shares outstanding in each period.

The pro forma results do not necessarily represent results which would have occurred if the acquisitions had taken place at the beginning of the periods indicated, nor are they indicative of the results of future combined operations.

- Definition

The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1497-128463

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Section 50
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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+ Details

Goodwill and Intangible Assets

12 Months Ended

Dec. 31, 2015

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets

7. Goodwill and Intangible Assets:

Goodwill was $3.4 billion and $2.8 billion at December 31, 2015 and 2014, respectively. The change in the carrying amount of goodwill of approximately $590.0 million during the year ended December 31, 2015 is primarily related to the Company’s 2015 acquisitions. The Company expects that approximately $83.7 million of the goodwill recorded during the year ended December 31, 2015 will be deductible for tax purposes. The change in the carrying amount of goodwill during the year ended December 31, 2014 of approximately $382.5 million related to the 2014 acquisitions.

Intangible assets, net, consist of the following (in thousands):


	December 31, 2015
	Gross Carrying Value		Accumulated Amortization			Net Carrying Value		Weighted Average Amortization Period (1) (in years)
Physician and hospital agreements	$	265,465	$	(130,050	)	$	135,415		0.4
Customer relationships		248,880		(10,612	)		238,268		9.9
Trade names		28,620		(597	)		28,023		1.2
Patented technology		24,230		(1,717	)		22,513		0.6

	$	567,195	$	(142,976	)	$	424,219

(1)	The weighted average amortization period includes amortization expense related to years beyond 2020 of approximately $229.3 million.


	December 31, 2014
	Gross Carrying Value		Accumulated Amortization			Net Carrying Value		Weighted Average Amortization Period (2) (in years)
Physician and hospital agreements	$	216,458	$	(98,145	)	$	118,313		0.8
Customer relationships		75,460		(2,634	)		72,826		7.2
Trade names		7,150		(153	)		6,997		0.7

	$	299,068	$	(100,932	)	$	198,136

(2)	The weighted average amortization period includes amortization expense related to years beyond 2019 of approximately $69.1 million.

The change in the carrying amount of intangible assets, net of approximately $226.1 million during the year ended December 31, 2015 is primarily related to the Company’s 2015 acquisitions.

Amortization expense for other intangible assets was $42.0 million, $30.1 million and $24.5 million for the years ended December 31, 2015, 2014 and 2013, respectively.

Amortization expense for existing other intangible assets for the next five years is expected to be as follows (in thousands):


2016	$	48,967
2017		43,173
2018		38,639
2019		34,600
2020		29,535

- Definition

The entire disclosure for the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain (loss) on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final. May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss.

+ References + Details

Accounts Payable and Accrued Expenses

12 Months Ended

Dec. 31, 2015

Payables and Accruals [Abstract]

Accounts Payable and Accrued Expenses

8. Accounts Payable and Accrued Expenses:

Accounts payable and accrued expenses consist of the following (in thousands):


	December 31,
	2015		2014
Accounts payable	$	21,969	$	32,783
Accrued salaries and bonuses		233,499		231,390
Accrued payroll taxes and benefits		58,979		49,858
Accrued professional liability		25,995		19,718
Accrued contingent consideration		13,565		17,010
Accrual for uncertain tax positions		7,000		—
Other accrued expenses		34,800		29,899

	$	395,807	$	380,658

Accrued Professional Liability

12 Months Ended

Dec. 31, 2015

Health Care Organizations [Abstract]

Accrued Professional Liability

9. Accrued Professional Liability:

At December 31, 2015 and 2014, the Company’s total accrued professional liability of $202.5 million and $168.4 million, respectively, includes incurred but not reported loss reserves of $142.4 million and $120.6 million, respectively, and loss reserves for reported claims associated with self-insured retention amounts through the Company’s wholly owned captive insurance subsidiary of $60.1 million and $47.8 million, respectively.

The activity related to the Company’s total accrued professional liability for the years ended December 31, 2015, 2014 and 2013 is as follows (in thousands):


	Years Ended December 31,
	2015			2014			2013
Balance at beginning of year	$	168,369		$	158,691		$	137,036
Assumed liabilities through acquisition		35,968			—			—

Provision (adjustment) for losses related to:
Current year		39,204			39,386			41,235
Prior years		(25,797	)		(16,125	)		(8,100	)

Total provision for losses		13,407			23,261			33,135

Claim payments related to:
Current year		(1,382	)		(293	)		(741	)
Prior years		(13,835	)		(13,290	)		(10,739	)

Total payments		(15,217	)		(13,583	)		(11,480	)

Balance at end of year	$	202,527		$	168,369		$	158,691

The net increases in the Company’s total accrued professional liability for the years ended December 31, 2015 and 2014, are primarily attributable to liabilities assumed through an acquisition and increases in the current year provision for losses as a result of the increase in the number of physicians insured due to acquisitions and internal growth, offset by claim payments and adjustments to the provision for losses related to prior years resulting from favorable trends in the Company’s claims experience.

- Definition

The entire disclosure for the accrual for malpractice loss contingencies (general and professional liability) which may include the policy used for accruing the loss contingency, the nature and amount of any accrual, and any significant estimate used to determine the accrual.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 450
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6491354&loc=d3e6052-115624

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14453-108349

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 450
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6491354&loc=d3e6049-115624

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14472-108349

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14394-108349

+ Details

Long-Term Debt and Capital Lease Obligations

12 Months Ended

Dec. 31, 2015

Debt Disclosure [Abstract]

Long-Term Debt and Capital Lease Obligations

10. Long-Term Debt and Capital Lease Obligations:

In June 2015, the Company entered into an amendment to its existing credit agreement dated as of October 29, 2014 (as amended, the “Credit Agreement”), in order to exercise the accordion feature and increase the total revolving loan commitments from $1.3 billion to $1.7 billion. The Credit Agreement provides for a $1.7 billion unsecured revolving credit facility and a $200.0 million term loan and includes a $75.0 million sub-facility for swingline loans and a $37.5 million sub-facility for the issuance of letters of credit. The Company may increase the Credit Agreement to up to $2.2 billion on an unsecured basis, subject to the satisfaction of specified conditions. The Credit Agreement matures on October 29, 2019 and is guaranteed by substantially all of the Company’s subsidiaries and affiliated professional contractors. At the Company’s option, borrowings under the Credit Agreement (other than swingline loans) will bear interest at (i) the Alternate Base Rate (defined as the higher of (a) the prime rate, (b) the Federal Funds Rate plus 1/2 of 1.00% and (c) LIBOR for an interest period of one month plus 1.00%) plus an applicable margin rate ranging from 0.125% to 0.750% based on the Company’s consolidated leverage ratio or (ii) the LIBOR rate plus an applicable margin rate ranging from 1.125% to 1.750% based on the Company’s consolidated leverage ratio. Swingline loans will bear interest at the alternate base rate plus the applicable margin. The Credit Agreement also calls for other customary fees and charges, including an unused commitment fee ranging from 0.150% to 0.300% of the unused lending commitments, based on the Company’s consolidated leverage ratio.

The Credit Agreement contains customary covenants and restrictions, including covenants that require the Company to maintain a minimum interest coverage ratio, not to exceed a specified consolidated leverage ratio and to comply with laws. The Credit Agreement permits the Company to pay dividends and make certain other distributions, subject to limitations specified therein. Failure to comply with these covenants would constitute an event of default under the Credit Agreement, notwithstanding the ability of the Company to meet its debt service obligations. The Credit Agreement also includes various customary remedies for the lenders following an event of default, including the acceleration of repayment of outstanding amounts under the Credit Agreement. At December 31, 2015, the Company believes it was in compliance, in all material respects, with the financial covenants and other restrictions applicable under the Credit Agreement.

On December 8, 2015, the Company completed a private offering of $750.0 million aggregate principal amount of 5.25% senior unsecured notes due 2023 (the “2023 Senior Notes”). The Company’s obligations under the 2023 Senior Notes are guaranteed on an unsecured senior basis by the same subsidiaries and affiliated professional contractors that guarantee the Credit Agreement. Interest on the 2023 Senior Notes accrues at the rate of 5.25% per annum and is payable semi-annually in arrears on June 1 and December 1, beginning on June 1, 2016.

At any time prior to December 1, 2018, the Company may redeem all or a portion of the 2023 Senior Notes at a redemption price equal to 100% of the principal amount of the notes being redeemed plus an applicable redemption premium and accrued and unpaid interest to the redemption date. In addition, at any time prior to December 1, 2018, the Company may redeem up to 35% of the aggregate principal amount of the 2023 Senior Notes at a redemption price of 105.250% of the principal amount thereof, plus accrued and unpaid interest, if any, to the redemption date, using proceeds from one or more equity offerings. On or after December 1, 2018, the Company may redeem all or a portion of the 2023 Senior Notes, at the redemption prices of 103.938% in 2018, 102.625% in 2019, 101.313% in 2020 and 100% in 2021 and thereafter, plus accrued and unpaid interest to the redemption date.

The indenture under which the 2023 Senior Notes are issued, among other things, limits our ability to (1) incur liens and (2) enter into sale and lease-back transactions, and also limits our ability to merge or dispose of all or substantially all of our assets, in all cases, subject to a number of customary exceptions. Although we are not required to make mandatory redemption or sinking fund payments with respect to the 2023 Senior Notes, upon the occurrence of a change in control of MEDNAX, we may be required to repurchase the 2023 Senior Notes at a purchase price equal to 101% of the aggregate principal amount of the 2023 Senior Notes repurchased plus accrued and unpaid interest.

As of December 31, 2015, the Company adopted the accounting guidance that issuance costs related to a recognized long-term debt liability, other than revolving credit arrangements, be presented in the balance sheet as a direct deduction from the carrying value of that long-term debt.

Long-term debt consists of the following (in thousands):


	December 31, 2015
	Principal			Unamortized Debt Issuance Costs			Total
5.25% Senior Unsecured Notes due 2023	$	750,000		$	(12,695	)	$	737,305
Revolving line of credit		343,500			—			343,500
Term loan		190,000			(401	)		189,599

		1,283,500			(13,096	)		1,270,404
Less: Current portion		(10,000	)		—			(10,000	)

Long-term portion	$	1,273,500		$	(13,096	)	$	1,260,404


	December 31, 2014
	Principal			Unamortized Debt Issuance Costs			Total
Revolving line of credit	$	368,000		$	—		$	368,000
Term loan		200,000			(547	)		199,453

		568,000			(547	)		567,453
Less: Current portion		(10,000	)		—			(10,000	)

Long-term portion	$	558,000		$	(547	)	$	557,453

The Company has outstanding letters of credit which reduced the amount available under the Credit Agreement by $0.2 million at December 31, 2015. At December 31, 2015, the Company had an available balance on its Credit Agreement of $1.4 billion.

Aggregate annual maturities of the Company’s term loan and 2023 Senior Notes as of December 31, 2015 are as follows (in thousands):


2016	$	10,000
2017		20,000
2018		30,000
2019		130,000
Thereafter		750,000

The Company’s capital lease obligations consist of the following (in thousands):


	December 31,
	2015			2014
Capital lease obligations	$	4,299		$	1,320
Less: Current portion		(1,883	)		(465	)

Long-term portion	$	2,416		$	855

The amounts due under the terms of the Company’s capital lease obligations at December 31, 2015 are as follows:


2016	$	1,883
2017		1,632
2018		738
2019		46

Income Taxes

12 Months Ended

Dec. 31, 2015

Income Tax Disclosure [Abstract]

Income Taxes

11. Income Taxes:

The components of the income tax provision are as follows (in thousands):


	December 31,
	2015		2014		2013
Federal:
Current	$	168,596	$	167,745	$	134,938
Deferred		12,866		2,262		14,784

		181,462		170,007		149,722

State:
Current		20,948		21,109		17,037
Deferred		1,628		297		1,136

		22,576		21,406		18,173

Total	$	204,038	$	191,413	$	167,895

The Company files its tax return on a consolidated basis with its subsidiaries. The remaining affiliated professional contractors file tax returns on an individual basis.

The effective tax rate was 37.76%, 37.63% and 37.44% for the years ended December 31, 2015, 2014 and 2013, respectively.

The differences between the effective rate and the United States federal income tax statutory rate are as follows:


	December 31,
	2015			2014			2013
Tax at statutory rate		35.00	%		35.00	%		35.00	%
State income tax, net of federal benefit		2.97			2.74			2.63
Non-deductible expenses		0.34			0.33			0.27
Change in accrual estimates relating to uncertain tax positions		(0.43	)		(0.59	)		(0.48	)
Change in valuation allowance		0.29			—			—
Other, net		(0.41	)		0.15			0.02

Income tax provision		37.76	%		37.63	%		37.44	%

The Company adopted the accounting guidance related to deferred income taxes, and accordingly, all deferred tax assets and liabilities are classified as long-term for the year ended December 31, 2015. The significant components of deferred income tax assets and liabilities are as follows (in thousands):


	December 31, 2015
Allowance for uncollectible accounts	$	82,928
Reserves and accruals		66,655
Stock-based compensation		13,662
Net operating loss carryforward		51,505
Property and equipment		3,116
Other		2,723

Deferred tax assets before valuation allowance		220,589
Less: Valuation allowance		(1,552	)

Deferred tax assets, net of valuation allowance		219,037

Gross deferred tax liabilities:
Amortization		(311,303	)
Accrual to cash adjustment		(55,046	)
Other		(6,693	)

Total deferred tax liabilities		(373,042	)

Net deferred tax liability	$	(154,005	)

Deferred income tax assets and liabilities have not been retrospectively classified as long-term for the year ended December 31, 2014. The significant components of deferred tax assets and liabilities for the year ended December 31, 2014 are as follows (in thousands):


	December 31, 2014
	Total			Current			Non- Current
Allowance for uncollectible accounts	$	48,178		$	48,178		$	—
Reserves and accruals		62,708			26,066			36,642
Stock-based compensation		14,354			8,346			6,008
Net operating loss carryforward		10,933			1,504			9,429
Property and equipment		1,524			—			1,524
Other		1,461			583			878

Total deferred tax assets		139,158			84,677			54,481

Amortization		(214,968	)		—			(214,968	)
Accrual to cash adjustment		(38,524	)		(38,524	)		—
Other		(192	)		(192	)		—

Total deferred tax liabilities		(253,684	)		(38,716	)		(214,968	)

Net deferred tax (liability) asset	$	(114,526	)	$	45,961		$	(160,487	)

The income tax benefit related to the exercise of stock options, the vesting of restricted and deferred stock and the purchase of shares under the Company’s non-qualified employee stock purchase plan in excess of amounts recorded as equity compensation expense reduces taxes currently payable and is credited to additional paid-in capital. Such amounts totaled approximately $11.6 million, $17.5 million, and $19.0 million for the years ended December 31, 2015, 2014 and 2013, respectively.

The Company has net operating loss carryforwards for federal and state tax purposes totaling approximately $136.6 million, $29.0 million, and $16.9 million at December 31, 2015, 2014 and 2013, respectively, expiring at various times in 2019 through 2035. The changes in net operating loss carryforwards in 2015 and 2014 are primarily due to timing differences related to the recognition of income for tax purposes associated with acquisitions.

As of December 31, 2015, 2014 and 2013, the Company’s liability for uncertain tax positions, excluding accrued interest and penalties, was $18.4 million, $17.2 million and $14.9 million, respectively. The Company had approximately $17.1 million of uncertain tax positions that, if recognized, would favorably impact its effective tax rate at December 31, 2015.

The following table summarizes the activity related to the Company’s liability for uncertain tax positions for the years ended December 31, 2015, 2014 and 2013 (in thousands):


	Years Ended December 31,
	2015			2014			2013
Balance at beginning of year	$	17,165		$	14,902		$	13,072
Increases related to prior year tax positions		467			40			338
Decreases related to prior year tax positions		(1,168	)		—			(38	)
Increases related to current year tax positions		3,675			3,750			2,955
Decreases related to lapse of statutes of limitations		(1,692	)		(1,527	)		(1,425	)

Balance at end of year	$	18,447		$	17,165		$	14,902

During the years ended December 31, 2015 and 2014, the Company increased its liability for uncertain tax positions by a total of $1.2 million and $2.3 million, respectively, primarily related to additional taxes on current year positions, partially offset by decreases due to the expiration of statutes of limitation and current year tax positions.

During the third quarter of 2015, the Company entered into settlement discussions with a taxing authority regarding a tax matter. In connection with these settlement discussions, the Company believes that it is reasonably possible that its liability for uncertain tax positions may be decreased by approximately $7.0 million to $9.0 million over the next 12 months, all of which would favorably impact the Company’s effective tax rate.

In addition, the Company anticipates that its liability for uncertain tax positions will be increased by approximately $2.5 million for additional taxes and decreased by approximately $1.9 million related to the expiration of certain statutes of limitation over the next 12 months.

The Company includes interest and penalties related to income tax liabilities in income tax expense. The Company recognized a net increase of $0.6 million and $0.3 million related to interest and penalties during the years ended December 31, 2015 and 2014, respectively. The Company recognized a net decrease of $0.6 million in interest and penalties related to income tax liabilities during the year ended December 31, 2013. At December 31, 2015 and 2014, the Company’s accrued liability for interest and penalties related to income tax liabilities totaled $9.3 million and $8.7 million, respectively.

The Company is currently subject to U.S. Federal and various state income tax examinations for the tax years 2004 through 2014.

Common and Common Equivalent Shares

12 Months Ended

Dec. 31, 2015

Earnings Per Share [Abstract]

Common and Common Equivalent Shares

12. Common and Common Equivalent Shares:

The calculation of shares used in the basic and diluted net income per share calculation for the years ended December 31, 2015, 2014 and 2013 is as follows (in thousands):


	Years Ended December 31,
	2015		2014		2013
Weighted average number of common shares outstanding		93,077		98,588		99,112
Weighted average number of dilutive common share equivalents		883		1,299		1,857

Weighted average number of common and common equivalent shares outstanding		93,960		99,887		100,969

Antidilutive securities not included in the diluted net income per common share calculation		—		1		35

Stock Incentive Plans and Stock Purchase Plans

12 Months Ended

Dec. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock Incentive Plans and Stock Purchase Plans

13. Stock Incentive Plans and Stock Purchase Plans:

The Company’s Amended and Restated 2008 Incentive Compensation Plan, as amended (the “Amended and Restated 2008 Incentive Plan”) provides for grants of stock options, stock appreciation rights, restricted stock, deferred stock, and other stock-related awards and performance awards that may be settled in cash, stock or other property.

Under the Amended and Restated 2008 Incentive Plan, options to purchase shares of common stock may be granted at a price not less than the fair market value of the shares on the date of grant. The options must be exercised within 10 years from the date of grant and generally become exercisable on a pro rata basis over a three-year period from the date of grant. The Company issues new shares of its common stock upon exercise of its stock options. Restricted stock awards generally vest over periods of three years upon the fulfillment of specified service-based conditions and in certain instances performance-based conditions. Deferred stock awards generally vest upon the satisfaction of specified performance-based conditions or service-based conditions. The Company recognizes compensation expense related to its restricted stock and deferred stock awards ratably over the corresponding vesting periods. At December 31, 2015, the Company had approximately 5.4 million shares available for future grants and awards under its Amended and Restated 2008 Incentive Plan.

On November 3, 2015, the Company’s shareholders approved an amendment to the Company’s 1996 Non-Qualified Employee Stock Purchase Plan, as amended (the “ESPP”) to increase the number of shares issuable under the ESPP. Under the ESPP, employees are permitted to purchase the Company’s common stock at 85% of market value on January 1st, April 1st, July 1st and October 1st of each year. Also on November 3, 2015, the Company’s shareholders approved the creation of the 2015 Non-Qualified Stock Purchase Plan (the “SPP”) which allows certain eligible non-employee service providers to purchase the Company’s common stock at 90% of market value on January 1st, April 1st, July 1st and October 1st of each year upon the SPP’s effective date of January 1, 2016.

Each of the ESPP and the SPP provide for the issuance of an of aggregate 2.5 million shares of the Company’s common stock less the number of shares of common stock purchased under the other plan. In accordance with the provisions of the accounting guidance for stock-based compensation, the Company recognizes stock-based compensation expense for the discount received by participating employees and non-employee service providers. During the year ended December 31, 2015, approximately 234,000 shares were issued under the ESPP. At December 31, 2015, the Company had approximately 2.6 million shares in aggregate reserved for issuance under the ESPP and SPP.

The Company recognized approximately $32.1 million, $31.7 million and $31.3 million of stock-based compensation expense related to its stock incentive plans and the ESPP during the years ended December 31, 2015, 2014 and 2013, respectively.

The activity related to the Company’s restricted and deferred stock awards and the corresponding weighted average grant-date fair values for the year ended December 31, 2015 are as follows:


	Number of Shares			Weighted Average Fair Value
Non-vested shares at January 1, 2015		1,271,044		$	46.80
Awarded		483,423		$	70.44
Forfeited		(29,974	)	$	55.77
Vested		(710,702	)	$	44.43

Non-vested shares at December 31, 2015		1,013,791		$	61.50

The aggregate fair value of the restricted and deferred stock that vested during the years ended December 31, 2015, 2014 and 2013 was approximately $31.6 million, $28.2 million and $33.3 million, respectively.

The weighted average grant-date fair value of restricted and deferred stock awards that were granted during the years ended December 31, 2015, 2014 and 2013 was $70.44, $57.73 and $46.48, respectively.

At December 31, 2015, the total stock-based compensation cost related to non-vested restricted stock remaining to be recognized as compensation expense over a weighted-average period of approximately 1.5 years was $28.7 million.

The Company did not grant any stock options during 2015 or 2014, and all stock-based compensation cost related to stock options has been recognized. The activity and certain other information related to the Company’s outstanding stock option awards for the year ended December 31, 2015 are as follows:


	Number of Stock Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in millions)
Outstanding at January 1, 2015		814,094		$	27.57
Exercised		(228,707	)	$	26.58			$	11.3

Outstanding and exercisable at December 31, 2015		585,387		$	27.96		2.7	$	25.6

The aggregate intrinsic value of stock options exercised during the years ended December 31, 2015, 2014 and 2013 was $25.6 million, $38.8 million and $35.4 million, respectively.

The net excess tax benefit recognized in additional paid-in capital related primarily to stock options, restricted stock and deferred stock for the years ended December 31, 2015, 2014 and 2013 was approximately $11.6 million, $17.5 million and $19.0 million, respectively. The cash proceeds received from the exercise of stock options for the years ended December 31, 2015, 2014 and 2013 were approximately $6.1 million, $30.1 million and $18.9 million, respectively.

Common Stock Repurchase Programs	12 Months Ended
Common Stock Repurchase Programs	Dec. 31, 2015
Text Block [Abstract]
Common Stock Repurchase Programs	14. Common Stock Repurchase Programs: In July 2013, the Company’s Board of Directors authorized the repurchase of shares of the Company’s common stock up to an amount sufficient to offset the dilutive impact from the issuance of shares under the Company’s equity compensation programs. The share repurchase program allows the Company to make open market purchases from time-to-time based on general economic and market conditions and trading restrictions. The repurchase program also allows for the repurchase of shares of the Company’s common stock to offset the dilutive impact from the issuance of shares, if any, related to the Company’s acquisition program. In October 2014, the Company announced that its Board of Directors had authorized the repurchase of up to $600.0 million of shares of the Company’s common stock in addition to its existing share repurchase program. In December 2014, the Company entered into uncollared accelerated share repurchase (“ASR”) agreement with an investment bank. Under the ASR agreement, the Company agreed to purchase $200.0 million of its common stock in total. On December 17, 2014, the Company paid a total of $200.0 million to an investment bank, which in turn delivered to the Company approximately 2.5 million shares of the Company’s common stock in total based on the market price of a share of Company common stock on December 12, 2014. The payment was recorded as a reduction to the respective components of shareholders’ equity. The final number of shares of common stock that the Company may receive, or may be required to remit, upon settlement under the ASR agreement was to be based upon the average daily volume weighted-average price of the Company’s common stock during the term of the ASR agreement, less a negotiated discount. The ASR agreement was funded by borrowings under the Company’s Credit Agreement discussed in Note 10. Final settlement of the ASR occurred in July 2015 with the delivery to the Company of 0.3 million additional shares of common stock. The final number of shares of common stock that the Company received was based upon the average daily volume weighted-average price of the Company’s common stock during the term of the ASR agreement, less a negotiated discount. In March 2015, the Company entered into a second uncollared ASR agreement with an investment bank. Under the ASR agreement, the Company agreed to purchase $200.0 million of its common stock in total. On March 16, 2015, the Company paid a total of $200.0 million to an investment bank, which in turn delivered to the Company approximately 2.2 million shares of the Company’s common stock in total based on the market price of a share of Company common stock on March 12, 2015. The ASR agreement was funded by borrowings under the Company’s Credit Agreement, and the payment was recorded as a reduction to the respective components of shareholders’ equity. Final settlement of the ASR occurred in October 2015 with the delivery to the Company of 0.3 million additional shares of common stock. The final number of shares of common stock that the Company received was based upon the average daily volume weighted-average price of the Company’s common stock during the term of the ASR agreement, less a negotiated discount. During the year ended December 31, 2015, the Company repurchased approximately 3.4 million shares of its common stock for approximately $235.1 million, inclusive of shares delivered to the Company under the ASR agreements, and 18,282 shares withheld to satisfy minimum stock withholding obligations of $1.5 million in connection with the vesting of restricted stock units. The Company intends to utilize various methods to effect any additional share repurchases, including, among others, open market purchases and accelerated share repurchase programs. The amount and timing of repurchases will depend upon several factors, including general economic and market conditions and trading restrictions.

Retirement Plans	12 Months Ended
Retirement Plans	Dec. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Retirement Plans	15. Retirement Plans: The Company maintains five qualified contributory savings plans as allowed under Section 401(k) of the Internal Revenue Code and Section 1165(e) of the Puerto Rico Income Tax Act of 1954 (the “401(k) Plans”). The 401(k) Plans permit participant contributions and allow elective and, in certain situations, non-elective Company contributions based on each participant’s contribution or a specified percentage of eligible wages. Participants may defer a percentage of their annual compensation subject to the limits defined in the 401(k) Plans. The Company recorded expense of $39.7 million, $34.3 million and $29.8 million for the years ended December 31, 2015, 2014 and 2013, respectively, primarily related to the 401(k) Plans.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2015

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

16. Commitments and Contingencies:

The Company expects that audits, inquiries and investigations from government authorities and agencies will occur in the ordinary course of business. Such audits, inquiries and investigations and their ultimate resolutions, individually or in the aggregate, could have a material adverse effect on the Company’s business, financial condition, results of operations, cash flows and the trading price of its common stock. The Company has not included an accrual for these matters as of December 31, 2015 in its Consolidated Financial Statements, as the variables affecting any potential eventual liability depend on the currently unknown facts and circumstances that arise out of, and are specific to, any particular future audit, inquiry and investigation and cannot be reasonably estimated at this time.

In the ordinary course of business, the Company becomes involved in pending and threatened legal actions and proceedings, most of which involve claims of medical malpractice related to medical services provided by the Company’s affiliated physicians. The Company’s contracts with hospitals generally require the Company to indemnify them and their affiliates for losses resulting from the negligence of the Company’s affiliated physicians. The Company may also become subject to other lawsuits which could involve large claims and significant costs. The Company believes, based upon a review of pending actions and proceedings, that the outcome of such legal actions and proceedings will not have a material adverse effect on its business, financial condition, results of operations, cash flows and the trading price of its securities. The outcome of such actions and proceedings, however, cannot be predicted with certainty and an unfavorable resolution of one or more of them could have a material adverse effect on the Company’s business, financial condition, results of operations, cash flows and the trading price of its securities.

Although the Company currently maintains liability insurance coverage intended to cover professional liability and certain other claims, the Company cannot assure that its insurance coverage will be adequate to cover liabilities arising out of claims asserted against it in the future where the outcomes of such claims are unfavorable. With respect to professional liability risk, the Company generally self-insures a portion of this risk through its wholly owned captive insurance subsidiary. Liabilities in excess of the Company’s insurance coverage, including coverage for professional liability and certain other claims, could have a material adverse effect on the Company’s business, financial condition, results of operations, cash flows and the trading price of its securities.

The Company leases space for its regional, medical and business offices, storage space and temporary housing of medical staff. The Company also leases an aircraft. Rent expense for the years ended December 31, 2015, 2014 and 2013 was approximately $31.6 million, $27.8 million, and $26.4 million, respectively.

Future minimum lease payments under non-cancelable operating leases as of December 31, 2015 are as follows (in thousands):


2016	$	29,856
2017		23,045
2018		17,856
2019		11,691
2020		7,402
Thereafter		11,911

	$	101,761

Selected Quarterly Financial Information

12 Months Ended

Dec. 31, 2015

Quarterly Financial Information Disclosure [Abstract]

Selected Quarterly Financial Information

17. Selected Quarterly Financial Information (Unaudited):

The following tables set forth a summary of the Company’s selected quarterly financial information for each of the four quarters ended December 31, 2015 and 2014 (in thousands, except for per share data):


	2015 Quarters
	First			Second			Third			Fourth
Net revenue	$	639,395		$	676,588		$	722,273		$	741,740

Operating expenses:
Practice salaries and benefits		419,595			422,803			450,033			461,074
Practice supplies and other operating expenses		23,431			24,878			24,007			26,164
General and administrative expenses		67,936			72,401			80,185			85,393
Depreciation and amortization		13,612			15,549			16,918			18,149

Total operating expenses		524,574			535,631			571,143			590,780

Income from operations		114,821			140,957			151,130			150,960
Investment and other income		142			384			567			751
Interest expense		(3,267	)		(5,149	)		(6,201	)		(8,493	)
Equity in earnings of unconsolidated affiliate		821			745			784			777

Total non-operating expenses		(2,304	)		(4,020	)		(4,850	)		(6,965	)
Income before income taxes		112,517			136,937			146,280			143,995
Income tax provision		43,928			52,889			55,640			51,581

Net income		68,589			84,048			90,640			92,414
Net loss attributable to noncontrolling interests		118			82			141			288

Net income attributable to MEDNAX, Inc.	$	68,707		$	84,130		$	90,781		$	92,702

Per common and common equivalent share data (1):
Net income attributable to MEDNAX, Inc.:
Basic	$	0.73		$	0.91		$	0.98		$	1.00

Diluted	$	0.72		$	0.90		$	0.97		$	0.99

Weighted average common shares:
Basic		94,231			92,500			92,949			92,790

Diluted		95,325			93,495			93,646			93,536

(1)	Basic and diluted per share amounts are computed for each of the periods presented. Accordingly, the sum of the quarterly per share amounts may not agree with the full year amount.


	2014 Quarters
	First			Second			Third			Fourth
Net revenue	$	566,338		$	595,544		$	626,506		$	650,525

Operating expenses:
Practice salaries and benefits		372,040			372,216			394,794			404,345
Practice supplies and other operating expenses		21,417			22,466			21,570			23,549
General and administrative expenses		58,414			60,829			60,643			67,641
Depreciation and amortization		10,370			10,361			11,356			13,903

Total operating expenses		462,241			465,872			488,363			509,438

Income from operations		104,097			129,672			138,143			141,087
Investment and other income		1,635			335			563			195
Interest expense		(1,371	)		(2,188	)		(2,019	)		(3,313	)
Equity in earnings of unconsolidated affiliate		—			150			725			905

Total non-operating expenses		264			(1,703	)		(731	)		(2,213	)
Income before income taxes		104,361			127,969			137,412			138,874
Income tax provision		40,701			48,944			51,174			50,594

Net income		63,660			79,025			86,238			88,280
Net (income) loss attributable to noncontrolling interests		—			(9	)		(31	)		118

Net income attributable to MEDNAX, Inc.	$	63,660		$	79,016		$	86,207		$	88,398

Per common and common equivalent share data (1):
Net income attributable to MEDNAX, Inc.:
Basic	$	0.64		$	0.80		$	0.87		$	0.90

Diluted	$	0.63		$	0.79		$	0.86		$	0.89

Weighted average common shares:
Basic		99,076			98,411			99,088			98,066

Diluted		100,696			99,866			100,145			99,129

(1)	Basic and diluted per share amounts are computed for each of the periods presented. Accordingly, the sum of the quarterly per share amounts may not agree with the full year amount.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2015

Accounting Policies [Abstract]

Principles of Presentation

Principles of Presentation


	December 31, 2014
	Previously Reported		Adjustment			As Revised
*Consolidated Balance Sheet:*
Other assets (noncurrent portion) (1)	$	235,425	$	(547	)	$	234,878
Total assets	$	3,608,795	$	(547	)	$	3,608,248
Long-term debt and capital lease obligations	$	190,855	$	(547	)	$	190,308
Total liabilities	$	1,343,229	$	(547	)	$	1,342,682

(1)	For the year ended December 31, 2014, the previously reported amount of other noncurrent assets included intangible assets, net of accumulated amortization and other noncurrent assets. For the year ended December 31, 2015, intangible assets and other noncurrent assets are separately presented.

Recently Adopted Accounting Pronouncements

Recently Adopted Accounting Pronouncements

New Accounting Pronouncements

New Accounting Pronouncements

Accounting Estimates and Assumptions

Accounting Estimates and Assumptions

Segment Reporting

Segment Reporting

The following table summarizes the Company’s net revenue by service line (in percentages):


	Years Ended December 31,
	2015			2014			2013
Neonatal and other pediatric subspecialties		44	%		50	%		52	%
Anesthesia		37	%		36	%		32	%
Maternal-fetal		9	%		9	%		11	%
Pediatric cardiology		4	%		4	%		5	%
Radiology		4	%		—			—
Other services		2	%		1	%		—

		100	%		100	%		100	%

Revenue Recognition

Revenue Recognition

Cash and Cash Equivalents

Cash and Cash Equivalents

Certain cash equivalents carried by the Company are subject to the fair value provisions of the accounting guidance for fair value measurements. See “Fair Value Measurements” below.

Investments

Investments

Property and Equipment

Property and Equipment

Business Acquisitions

Business Acquisitions

Goodwill and Other Intangible Assets

Goodwill and Other Intangible Assets

Long-Lived Assets

Long-Lived Assets

Common Stock Repurchases

Common Stock Repurchases

Professional Liability Coverage

Professional Liability Coverage

Income Taxes

Income Taxes

Stock Incentive Plans

Stock Incentive Plans

Net Income Per Common Share

Net Income Per Common Share

Fair Value Measurements

Fair Value Measurements

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2015

Accounting Policies [Abstract]

Impact of Adjustments Made to Prior Period Balance Sheet

The impact of the adjustments made to prior period balance sheet is presented below (in thousands):


	December 31, 2014
	Previously Reported		Adjustment			As Revised
*Consolidated Balance Sheet:*
Other assets (noncurrent portion) (1)	$	235,425	$	(547	)	$	234,878
Total assets	$	3,608,795	$	(547	)	$	3,608,248
Long-term debt and capital lease obligations	$	190,855	$	(547	)	$	190,308
Total liabilities	$	1,343,229	$	(547	)	$	1,342,682

(1)	For the year ended December 31, 2014, the previously reported amount of other noncurrent assets included intangible assets, net of accumulated amortization and other noncurrent assets. For the year ended December 31, 2015, intangible assets and other noncurrent assets are separately presented.

Schedule of Net Revenue by Service Line

The following table summarizes the Company’s net revenue by service line (in percentages):


	Years Ended December 31,
	2015			2014			2013
Neonatal and other pediatric subspecialties		44	%		50	%		52	%
Anesthesia		37	%		36	%		32	%
Maternal-fetal		9	%		9	%		11	%
Pediatric cardiology		4	%		4	%		5	%
Radiology		4	%		—			—
Other services		2	%		1	%		—

		100	%		100	%		100	%

Investments (Tables)

12 Months Ended

Dec. 31, 2015

Investments, Debt and Equity Securities [Abstract]

Schedule of Investments

Investments held are summarized as follows (in thousands):


	December 31, 2015				December 31, 2014
	Short-Term		Long-Term		Short-Term		Long-Term
Municipal debt securities	$	8,608	$	34,858	$	5,539	$	35,827
Federal home loan securities		—		26,715		—		27,030
Certificates of deposit		245		1,715		496		1,225

	$	8,853	$	63,288	$	6,035	$	64,082

Schedule of Contractual Maturities of Long-Term Investments

Contractual maturities of long-term investments are summarized as follows (in thousands):


	December 31,
	2015		2014
Due after one year through five years	$	60,383	$	54,959
Due after five years through six years		2,905		9,123

	$	63,288	$	64,082

- Definition

Tabular disclosure of all investments in certain debt and equity securities for which the entity has the positive intent and ability to hold until maturity.

+ References + Details

Accounts Receivable and Net Revenue (Tables)

12 Months Ended

Dec. 31, 2015

Receivables [Abstract]

Schedule of Accounts Receivable, Net

Accounts receivable, net consists of the following (in thousands):


	December 31,
	2015			2014
Gross accounts receivable	$	1,574,038		$	1,200,958
Allowance for contractual adjustments and uncollectibles		(1,129,301	)		(848,767	)

	$	444,737		$	352,191

Schedule of Net Revenue

Net revenue consists of the following (in thousands):


	Years Ended December 31,
	2015			2014			2013
Gross revenue	$	8,942,957		$	7,662,556		$	6,702,484
Contractual adjustments and uncollectibles		(6,389,195	)		(5,403,437	)		(4,695,232	)
Hospital contract administrative fees		226,234			179,794			146,760

	$	2,779,996		$	2,438,913		$	2,154,012

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2015

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment

Property and equipment consists of the following (in thousands):


	December 31,
	2015			2014
Building	$	26,382		$	22,981
Land		6,683			6,683
Equipment and other		169,903			133,279

		202,968			162,943
Accumulated depreciation		(119,334	)		(96,895	)

	$	83,634		$	66,048

Business Acquisitions (Tables)

12 Months Ended

Dec. 31, 2015

Business Combinations [Abstract]

Summary of Company's Allocation of Purchase Price

The Company’s allocation of purchase price is as follows (in thousands):


	Radiology Acquisition			Other Acquisitions			Total
Current assets	$	51,736		$	11,445		$	63,181
Property and equipment		11,398			449			11,847
Other noncurrent assets		8,237			2,552			10,789
Goodwill		313,340			275,984			589,324
Other intangible assets		199,960			73,477			273,437
Current liabilities		(27,008	)		(1,160	)		(28,168	)
Deferred income tax liabilities—long-term		(15,850	)		(14,356	)		(30,206	)
Other long-term liabilities		(34,275	)		(2,618	)		(36,893	)

	$	507,538		$	345,773		$	853,311

Schedule of Pro Forma Information Combines Consolidated Results of Company and Business Acquisitions

The following unaudited pro forma information combines the consolidated results of operations of the Company on a GAAP basis and the acquisitions completed during 2015 and 2014, including adjustments for pro forma amortization and interest expense, as if the transactions had occurred on January 1, 2014 and January 1, 2013, respectively (in thousands, except per share data):


	Years Ended December 31,
	2015		2014
Net revenue	$	2,946,467	$	2,945,493
Net income		343,575		345,517
Net income per common share (1):
Basic	$	3.69	$	3.50
Diluted	$	3.66	$	3.46
Weighted average common shares (1):
Basic		93,077		98,588
Diluted		93,960		99,887

(1)	The comparison of net income per common share is affected by the changes in the number of weighted average shares outstanding in each period.

Goodwill and Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2015

Goodwill and Intangible Assets Disclosure [Abstract]

Summary of Intangible Assets, Net

Intangible assets, net, consist of the following (in thousands):


	December 31, 2015
	Gross Carrying Value		Accumulated Amortization			Net Carrying Value		Weighted Average Amortization Period (1) (in years)
Physician and hospital agreements	$	265,465	$	(130,050	)	$	135,415		0.4
Customer relationships		248,880		(10,612	)		238,268		9.9
Trade names		28,620		(597	)		28,023		1.2
Patented technology		24,230		(1,717	)		22,513		0.6

	$	567,195	$	(142,976	)	$	424,219

(1)	The weighted average amortization period includes amortization expense related to years beyond 2020 of approximately $229.3 million.


	December 31, 2014
	Gross Carrying Value		Accumulated Amortization			Net Carrying Value		Weighted Average Amortization Period (2) (in years)
Physician and hospital agreements	$	216,458	$	(98,145	)	$	118,313		0.8
Customer relationships		75,460		(2,634	)		72,826		7.2
Trade names		7,150		(153	)		6,997		0.7

	$	299,068	$	(100,932	)	$	198,136

(2)	The weighted average amortization period includes amortization expense related to years beyond 2019 of approximately $69.1 million.

Amortization Expenses for Existing Other Intangible Assets for the Next Five Years

Amortization expense for existing other intangible assets for the next five years is expected to be as follows (in thousands):


2016	$	48,967
2017		43,173
2018		38,639
2019		34,600
2020		29,535

Accounts Payable and Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2015

Payables and Accruals [Abstract]

Schedule of Accounts Payable and Accrued Expenses

Accounts payable and accrued expenses consist of the following (in thousands):


	December 31,
	2015		2014
Accounts payable	$	21,969	$	32,783
Accrued salaries and bonuses		233,499		231,390
Accrued payroll taxes and benefits		58,979		49,858
Accrued professional liability		25,995		19,718
Accrued contingent consideration		13,565		17,010
Accrual for uncertain tax positions		7,000		—
Other accrued expenses		34,800		29,899

	$	395,807	$	380,658

Accrued Professional Liability (Tables)

12 Months Ended

Dec. 31, 2015

Health Care Organizations [Abstract]

Schedule of Accrued Professional Liability

The activity related to the Company’s total accrued professional liability for the years ended December 31, 2015, 2014 and 2013 is as follows (in thousands):


	Years Ended December 31,
	2015			2014			2013
Balance at beginning of year	$	168,369		$	158,691		$	137,036
Assumed liabilities through acquisition		35,968			—			—

Provision (adjustment) for losses related to:
Current year		39,204			39,386			41,235
Prior years		(25,797	)		(16,125	)		(8,100	)

Total provision for losses		13,407			23,261			33,135

Claim payments related to:
Current year		(1,382	)		(293	)		(741	)
Prior years		(13,835	)		(13,290	)		(10,739	)

Total payments		(15,217	)		(13,583	)		(11,480	)

Balance at end of year	$	202,527		$	168,369		$	158,691

Long-Term Debt and Capital Lease Obligations (Tables)

12 Months Ended

Dec. 31, 2015

Debt Disclosure [Abstract]

Schedule of Long-Term Debt

Long-term debt consists of the following (in thousands):


	December 31, 2015
	Principal			Unamortized Debt Issuance Costs			Total
5.25% Senior Unsecured Notes due 2023	$	750,000		$	(12,695	)	$	737,305
Revolving line of credit		343,500			—			343,500
Term loan		190,000			(401	)		189,599

		1,283,500			(13,096	)		1,270,404
Less: Current portion		(10,000	)		—			(10,000	)

Long-term portion	$	1,273,500		$	(13,096	)	$	1,260,404


	December 31, 2014
	Principal			Unamortized Debt Issuance Costs			Total
Revolving line of credit	$	368,000		$	—		$	368,000
Term loan		200,000			(547	)		199,453

		568,000			(547	)		567,453
Less: Current portion		(10,000	)		—			(10,000	)

Long-term portion	$	558,000		$	(547	)	$	557,453

Schedule of Aggregate Annual Maturities of Term Loan and 2023 Senior Notes

Aggregate annual maturities of the Company’s term loan and 2023 Senior Notes as of December 31, 2015 are as follows (in thousands):


2016	$	10,000
2017		20,000
2018		30,000
2019		130,000
Thereafter		750,000

Schedule of Capital Lease Obligations

The Company’s capital lease obligations consist of the following (in thousands):


	December 31,
	2015			2014
Capital lease obligations	$	4,299		$	1,320
Less: Current portion		(1,883	)		(465	)

Long-term portion	$	2,416		$	855

Schedule of Amounts Due Under Terms of Capital Lease Obligations

The amounts due under the terms of the Company’s capital lease obligations at December 31, 2015 are as follows:


2016	$	1,883
2017		1,632
2018		738
2019		46

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2015

Income Tax Disclosure [Abstract]

Summary of Components of Income Tax Provision

The components of the income tax provision are as follows (in thousands):


	December 31,
	2015		2014		2013
Federal:
Current	$	168,596	$	167,745	$	134,938
Deferred		12,866		2,262		14,784

		181,462		170,007		149,722

State:
Current		20,948		21,109		17,037
Deferred		1,628		297		1,136

		22,576		21,406		18,173

Total	$	204,038	$	191,413	$	167,895

Schedule of Differences Between Effective Rate and United States Federal Income Tax Statutory Rate

The differences between the effective rate and the United States federal income tax statutory rate are as follows:


	December 31,
	2015			2014			2013
Tax at statutory rate		35.00	%		35.00	%		35.00	%
State income tax, net of federal benefit		2.97			2.74			2.63
Non-deductible expenses		0.34			0.33			0.27
Change in accrual estimates relating to uncertain tax positions		(0.43	)		(0.59	)		(0.48	)
Change in valuation allowance		0.29			—			—
Other, net		(0.41	)		0.15			0.02

Income tax provision		37.76	%		37.63	%		37.44	%

Significant Components of Deferred Income Tax Assets And Liabilities

The significant components of deferred income tax assets and liabilities are as follows (in thousands):


	December 31, 2015
Allowance for uncollectible accounts	$	82,928
Reserves and accruals		66,655
Stock-based compensation		13,662
Net operating loss carryforward		51,505
Property and equipment		3,116
Other		2,723

Deferred tax assets before valuation allowance		220,589
Less: Valuation allowance		(1,552	)

Deferred tax assets, net of valuation allowance		219,037

Gross deferred tax liabilities:
Amortization		(311,303	)
Accrual to cash adjustment		(55,046	)
Other		(6,693	)

Total deferred tax liabilities		(373,042	)

Net deferred tax liability	$	(154,005	)

The significant components of deferred tax assets and liabilities for the year ended December 31, 2014 are as follows (in thousands):


	December 31, 2014
	Total			Current			Non- Current
Allowance for uncollectible accounts	$	48,178		$	48,178		$	—
Reserves and accruals		62,708			26,066			36,642
Stock-based compensation		14,354			8,346			6,008
Net operating loss carryforward		10,933			1,504			9,429
Property and equipment		1,524			—			1,524
Other		1,461			583			878

Total deferred tax assets		139,158			84,677			54,481

Amortization		(214,968	)		—			(214,968	)
Accrual to cash adjustment		(38,524	)		(38,524	)		—
Other		(192	)		(192	)		—

Total deferred tax liabilities		(253,684	)		(38,716	)		(214,968	)

Net deferred tax (liability) asset	$	(114,526	)	$	45,961		$	(160,487	)

Schedule of Activity Related to Gross Unrecognized Tax Benefits

The following table summarizes the activity related to the Company’s liability for uncertain tax positions for the years ended December 31, 2015, 2014 and 2013 (in thousands):


	Years Ended December 31,
	2015			2014			2013
Balance at beginning of year	$	17,165		$	14,902		$	13,072
Increases related to prior year tax positions		467			40			338
Decreases related to prior year tax positions		(1,168	)		—			(38	)
Increases related to current year tax positions		3,675			3,750			2,955
Decreases related to lapse of statutes of limitations		(1,692	)		(1,527	)		(1,425	)

Balance at end of year	$	18,447		$	17,165		$	14,902

Common and Common Equivalent Shares (Tables)

12 Months Ended

Dec. 31, 2015

Earnings Per Share [Abstract]

Schedule of Calculation of Shares Used in Basic and Diluted Net Income Per Share

The calculation of shares used in the basic and diluted net income per share calculation for the years ended December 31, 2015, 2014 and 2013 is as follows (in thousands):


	Years Ended December 31,
	2015		2014		2013
Weighted average number of common shares outstanding		93,077		98,588		99,112
Weighted average number of dilutive common share equivalents		883		1,299		1,857

Weighted average number of common and common equivalent shares outstanding		93,960		99,887		100,969

Antidilutive securities not included in the diluted net income per common share calculation		—		1		35

Stock Incentive Plans and Stock Purchase Plans (Tables)

12 Months Ended

Dec. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Weighted Average Grant-Date Fair Values

The activity related to the Company’s restricted and deferred stock awards and the corresponding weighted average grant-date fair values for the year ended December 31, 2015 are as follows:


	Number of Shares			Weighted Average Fair Value
Non-vested shares at January 1, 2015		1,271,044		$	46.80
Awarded		483,423		$	70.44
Forfeited		(29,974	)	$	55.77
Vested		(710,702	)	$	44.43

Non-vested shares at December 31, 2015		1,013,791		$	61.50

Schedule of Activity and Certain Other Information Related to Stock Option Awards

The activity and certain other information related to the Company’s outstanding stock option awards for the year ended December 31, 2015 are as follows:


	Number of Stock Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in millions)
Outstanding at January 1, 2015		814,094		$	27.57
Exercised		(228,707	)	$	26.58			$	11.3

Outstanding and exercisable at December 31, 2015		585,387		$	27.96		2.7	$	25.6

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2015

Commitments and Contingencies Disclosure [Abstract]

Schedule of Future Minimum Lease Payments under Non-Cancelable Operating Leases

Future minimum lease payments under non-cancelable operating leases as of December 31, 2015 are as follows (in thousands):


2016	$	29,856
2017		23,045
2018		17,856
2019		11,691
2020		7,402
Thereafter		11,911

	$	101,761

Selected Quarterly Financial Information (Tables)

12 Months Ended

Dec. 31, 2015

Quarterly Financial Information Disclosure [Abstract]

Summary of Company's Selected Quarterly Financial Information


	2015 Quarters
	First			Second			Third			Fourth
Net revenue	$	639,395		$	676,588		$	722,273		$	741,740

Operating expenses:
Practice salaries and benefits		419,595			422,803			450,033			461,074
Practice supplies and other operating expenses		23,431			24,878			24,007			26,164
General and administrative expenses		67,936			72,401			80,185			85,393
Depreciation and amortization		13,612			15,549			16,918			18,149

Total operating expenses		524,574			535,631			571,143			590,780

Income from operations		114,821			140,957			151,130			150,960
Investment and other income		142			384			567			751
Interest expense		(3,267	)		(5,149	)		(6,201	)		(8,493	)
Equity in earnings of unconsolidated affiliate		821			745			784			777

Total non-operating expenses		(2,304	)		(4,020	)		(4,850	)		(6,965	)
Income before income taxes		112,517			136,937			146,280			143,995
Income tax provision		43,928			52,889			55,640			51,581

Net income		68,589			84,048			90,640			92,414
Net loss attributable to noncontrolling interests		118			82			141			288

Net income attributable to MEDNAX, Inc.	$	68,707		$	84,130		$	90,781		$	92,702

Per common and common equivalent share data (1):
Net income attributable to MEDNAX, Inc.:
Basic	$	0.73		$	0.91		$	0.98		$	1.00

Diluted	$	0.72		$	0.90		$	0.97		$	0.99

Weighted average common shares:
Basic		94,231			92,500			92,949			92,790

Diluted		95,325			93,495			93,646			93,536

(1)	Basic and diluted per share amounts are computed for each of the periods presented. Accordingly, the sum of the quarterly per share amounts may not agree with the full year amount.


	2014 Quarters
	First			Second			Third			Fourth
Net revenue	$	566,338		$	595,544		$	626,506		$	650,525

Operating expenses:
Practice salaries and benefits		372,040			372,216			394,794			404,345
Practice supplies and other operating expenses		21,417			22,466			21,570			23,549
General and administrative expenses		58,414			60,829			60,643			67,641
Depreciation and amortization		10,370			10,361			11,356			13,903

Total operating expenses		462,241			465,872			488,363			509,438

Income from operations		104,097			129,672			138,143			141,087
Investment and other income		1,635			335			563			195
Interest expense		(1,371	)		(2,188	)		(2,019	)		(3,313	)
Equity in earnings of unconsolidated affiliate		—			150			725			905

Total non-operating expenses		264			(1,703	)		(731	)		(2,213	)
Income before income taxes		104,361			127,969			137,412			138,874
Income tax provision		40,701			48,944			51,174			50,594

Net income		63,660			79,025			86,238			88,280
Net (income) loss attributable to noncontrolling interests		—			(9	)		(31	)		118

Net income attributable to MEDNAX, Inc.	$	63,660		$	79,016		$	86,207		$	88,398

Per common and common equivalent share data (1):
Net income attributable to MEDNAX, Inc.:
Basic	$	0.64		$	0.80		$	0.87		$	0.90

Diluted	$	0.63		$	0.79		$	0.86		$	0.89

Weighted average common shares:
Basic		99,076			98,411			99,088			98,066

Diluted		100,696			99,866			100,145			99,129

(1)	Basic and diluted per share amounts are computed for each of the periods presented. Accordingly, the sum of the quarterly per share amounts may not agree with the full year amount.

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Jun. 01, 2014
Summary Of Significant Accounting Policies [Line Items]
Additional amounts to be paid in cash or common stock based on achievement of performance measures within period, maximum years	5 years
Money market funds carrying amount	$ 13.9	$ 5.1
Carrying amount of cash surrender value of life insurance	14.5	16.0
Contingent consideration liabilities related to acquisitions, fair value	$ 24.9	$ 35.3
Variable Interest Entity, Primary Beneficiary [Member]
Summary Of Significant Accounting Policies [Line Items]
Consolidation method ownership percentage in joint venture	75.00%		75.00%
Unnamed Corporate Joint Venture [Member]
Summary Of Significant Accounting Policies [Line Items]
Equity method ownership percentage in joint venture	37.50%		37.50%
Government Contracts Concentration Risk [Member] \| Accounts Receivable [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of net accounts receivable	19.00%	19.00%
Buildings [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives, years	20 years
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Long-term investments maturity period, in years	6 years
Short-Term investments maturity period, in years	1 year
Intangible assets finite lives	20 years
Maximum [Member] \| Medical Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives, years	10 years
Maximum [Member] \| Computer Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives, years	10 years
Maximum [Member] \| Software and Software Development Costs [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives, years	10 years
Maximum [Member] \| Furniture [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives, years	10 years
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Long-term investments maturity period, in years	1 year
Intangible assets finite lives	1 year
Minimum [Member] \| Medical Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives, years	3 years
Minimum [Member] \| Computer Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives, years	3 years
Minimum [Member] \| Software and Software Development Costs [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives, years	3 years
Minimum [Member] \| Furniture [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives, years	3 years

Summary of Significant Accounting Policies - Impact of Adjustments Made to Prior Period Balance Sheet (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other assets (noncurrent portion)		$ 234,878
Total assets	$ 4,547,214	3,608,248
Long-term debt and capital lease obligations	919,320	190,308
Total liabilities	$ 2,109,368	1,342,682
Previously Reported [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other assets (noncurrent portion)		235,425
Total assets		3,608,795
Long-term debt and capital lease obligations		190,855
Total liabilities		1,343,229
Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other assets (noncurrent portion)		(547)
Total assets		(547)
Long-term debt and capital lease obligations		(547)
Total liabilities		$ (547)

Summary of Significant Accounting Policies - Schedule of Net Revenue by Service Line (Detail) - Product Concentration Risk [Member] - Sales Revenue, Services, Net [Member]	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Net revenue in percentage	100.00%	100.00%	100.00%
Neonatal and Other Pediatric Subspecialties [Member]
Segment Reporting Information [Line Items]
Net revenue in percentage	44.00%	50.00%	52.00%
Anesthesia [Member]
Segment Reporting Information [Line Items]
Net revenue in percentage	37.00%	36.00%	32.00%
Maternal-Fetal [Member]
Segment Reporting Information [Line Items]
Net revenue in percentage	9.00%	9.00%	11.00%
Pediatric Cardiology [Member]
Segment Reporting Information [Line Items]
Net revenue in percentage	4.00%	4.00%	5.00%
Radiology [Member]
Segment Reporting Information [Line Items]
Net revenue in percentage	4.00%
Other Services [Member]
Segment Reporting Information [Line Items]
Net revenue in percentage	2.00%	1.00%

Investments - Schedule of Investments (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Held-to-maturity Securities [Line Items]
Short-Term	$ 8,853	$ 6,035
Long-Term	63,288	64,082
Municipal Debt Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Short-Term	8,608	5,539
Long-Term	34,858	35,827
Federal Home Loan Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Long-Term	26,715	27,030
Certificates of Deposit [Member]
Schedule of Held-to-maturity Securities [Line Items]
Short-Term	245	496
Long-Term	$ 1,715	$ 1,225

Investments - Schedule of Contractual Maturities of Long-Term Investments (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Due after one year through five years	$ 60,383	$ 54,959
Due after five years through six years	2,905	9,123
Total	$ 63,288	$ 64,082

Accounts Receivable and Net Revenue - Schedule of Accounts Receivable, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Receivables [Abstract]
Gross accounts receivable	$ 1,574,038	$ 1,200,958
Allowance for contractual adjustments and uncollectibles	(1,129,301)	(848,767)
Accounts receivable, net	$ 444,737	$ 352,191

Accounts Receivable and Net Revenue - Schedule of Net Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Receivables [Abstract]
Gross revenue									$ 8,942,957	$ 7,662,556	$ 6,702,484
Contractual adjustments and uncollectibles									(6,389,195)	(5,403,437)	(4,695,232)
Hospital contract administrative fees									226,234	179,794	146,760
Net revenue	$ 741,740	$ 722,273	$ 676,588	$ 639,395	$ 650,525	$ 626,506	$ 595,544	$ 566,338	$ 2,779,996	$ 2,438,913	$ 2,154,012

Accounts Receivable and Net Revenue - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Receivables [Abstract]
Accounts receivable, net	$ 444,737				$ 352,191				$ 444,737	$ 352,191
Net patient service revenue	$ 741,740	$ 722,273	$ 676,588	$ 639,395	$ 650,525	$ 626,506	$ 595,544	$ 566,338	$ 2,779,996	$ 2,438,913	$ 2,154,012

Property and Equipment - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Building	$ 26,382	$ 22,981
Land	6,683	6,683
Equipment and other	169,903	133,279
Property and equipment, gross	202,968	162,943
Accumulated depreciation	(119,334)	(96,895)
Property and equipment, net	$ 83,634	$ 66,048

Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Medical and other equipment held under capital leases	$ 202,968	$ 162,943
Accumulated depreciation of property and equipment held under capital leases	119,334	96,895
Recorded depreciation expense	22,200	15,900	$ 15,500
Medical and Other Equipment [Member]
Property, Plant and Equipment [Line Items]
Medical and other equipment held under capital leases	5,400	2,400
Accumulated depreciation of property and equipment held under capital leases	$ 2,300	$ 1,400

Business Acquisitions - Additional Information (Detail)	12 Months Ended
Business Acquisitions - Additional Information (Detail)	Dec. 31, 2015 USD ($) Acquisition Company shares	Dec. 31, 2014 USD ($) Acquisition Company	Jun. 30, 2014 JointVenture	Jun. 01, 2014
Business Acquisition [Line Items]
Number of physician group practices acquired \| Company	10	11
Business acquisition, total consideration	$ 853,300,000	$ 488,600,000
Payments to acquire business, net of cash acquired	818,300,000	479,400,000
Contingent consideration	$ 3,800,000	$ 9,200,000
Number of anesthesiology practices acquired \| Company	7
Number of neonatology practices acquired \| Company	2
Number of other pediatric subspecialty practices acquired \| Company	1
Number of non-practice acquisitions \| Acquisition	2
Number of business acquired \| Acquisition	12	13
Cash acquired from acquisition	$ 23,000,000
Business acquisition, other current liabilities	400,000
Payments to acquire business by issue of common stock	$ 7,800,000
Number of shares of common stock issued \| shares	114,306
Time period for achievement of certain performance measures for payment of contingent consideration, years	2 years
Assumed payment probability of contingent consideration payment	100.00%
Range of the undiscounted amount under contingent consideration agreement, low	$ 0
Range of the undiscounted amount under contingent consideration agreement, high	4,000,000
Contingent consideration decrease in fair value	1,000,000
Contingent consideration payments related to prior-period acquisitions	14,300,000
Goodwill	3,366,150,000	$ 2,776,188,000
Number of joint ventures \| JointVenture			2
Fair value, contribution credit	7,700,000
Carrying value of goodwill transferred	7,200,000
Fixed assets transferred	500,000
Gain or loss from the joint venture transaction	$ 0
Variable Interest Entity, Primary Beneficiary [Member]
Business Acquisition [Line Items]
Consolidation method ownership percentage in joint venture	75.00%			75.00%
Unnamed Corporate Joint Venture [Member]
Business Acquisition [Line Items]
Equity method ownership percentage in joint venture	37.50%			37.50%
Prior-Period Acquisitions [Member]
Business Acquisition [Line Items]
Goodwill	$ 600,000
Other intangible assets	5,300,000
Other long-term liabilities	2,600,000
Additional cash consideration related to a working capital	600,000
Other current assets	$ 2,600,000
Minimum [Member]
Business Acquisition [Line Items]
Assumed discount rates for acquisition-date fair value	2.80%
Maximum [Member]
Business Acquisition [Line Items]
Assumed discount rates for acquisition-date fair value	3.50%

Business Acquisitions - Summary of Company's Allocation of Purchase Price (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill	$ 3,366,150	$ 2,776,188
Radiology Acquisition [Member]
Business Acquisition [Line Items]
Current assets	51,736
Property and equipment	11,398
Other noncurrent assets	8,237
Goodwill	313,340
Other intangible assets	199,960
Current liabilities	(27,008)
Deferred income tax liabilities-long-term	(15,850)
Other long-term liabilities	(34,275)
Total assets and liabilities	507,538
Other Acquisition [Member]
Business Acquisition [Line Items]
Current assets	11,445
Property and equipment	449
Other noncurrent assets	2,552
Goodwill	275,984
Other intangible assets	73,477
Current liabilities	(1,160)
Deferred income tax liabilities-long-term	(14,356)
Other long-term liabilities	(2,618)
Total assets and liabilities	345,773
Radiology Physician Services and Telemedicine Company [Member]
Business Acquisition [Line Items]
Current assets	63,181
Property and equipment	11,847
Other noncurrent assets	10,789
Goodwill	589,324
Other intangible assets	273,437
Current liabilities	(28,168)
Deferred income tax liabilities-long-term	(30,206)
Other long-term liabilities	(36,893)
Total assets and liabilities	$ 853,311

Business Acquisitions - Schedule of Pro Forma Information Combines Consolidated Results of Company and Business Acquisitions (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Business Combinations [Abstract]
Net revenue	$ 2,946,467	$ 2,945,493
Net income	$ 343,575	$ 345,517
Net income per common share, Basic	$ 3.69	$ 3.50
Net income per common share, Diluted	$ 3.66	$ 3.46
Weighted average common shares, Basic	93,077	98,588
Weighted average common shares, Diluted	93,960	99,887

Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 3,366,150	$ 2,776,188
Change in goodwill carrying amount	590,000	382,500
Goodwill deductible for tax purpose	83,700
Change in carrying amount of intangible assets, net	226,100
Amortization expense for existing other intangible assets	$ 42,000	$ 30,100	$ 24,500

Goodwill and Intangible Assets - Summary of Intangible Assets, Net (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 567,195	$ 299,068
Accumulated Amortization	(142,976)	(100,932)
Net Carrying Value	424,219	198,136
Physician And Hospital Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	265,465	216,458
Accumulated Amortization	(130,050)	(98,145)
Net Carrying Value	$ 135,415	$ 118,313
Weighted Average Amortization Period (in years)	4 months 24 days	9 months 18 days
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 248,880	$ 75,460
Accumulated Amortization	(10,612)	(2,634)
Net Carrying Value	$ 238,268	$ 72,826
Weighted Average Amortization Period (in years)	9 years 10 months 24 days	7 years 2 months 12 days
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 28,620	$ 7,150
Accumulated Amortization	(597)	(153)
Net Carrying Value	$ 28,023	$ 6,997
Weighted Average Amortization Period (in years)	1 year 2 months 12 days	8 months 12 days
Patented Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 24,230
Accumulated Amortization	(1,717)
Net Carrying Value	$ 22,513
Weighted Average Amortization Period (in years)	7 months 6 days

Goodwill and Intangible Assets - Amortization Expenses for Existing Other Intangible Assets for the Next Five Years (Detail) $ in Thousands	Dec. 31, 2015 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense for existing other intangible assets, 2016	$ 48,967
Amortization expense for existing other intangible assets, 2017	43,173
Amortization expense for existing other intangible assets, 2018	38,639
Amortization expense for existing other intangible assets, 2019	34,600
Amortization expense for existing other intangible assets, 2020	$ 29,535

Accounts Payable and Accrued Expenses - Schedule of Accounts Payable and Accrued Expenses (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Accounts payable	$ 21,969	$ 32,783
Accrued salaries and bonuses	233,499	231,390
Accrued payroll taxes and benefits	58,979	49,858
Accrued professional liability	25,995	19,718
Accrued contingent consideration	13,565	17,010
Accrual for uncertain tax positions	7,000
Other accrued expenses	34,800	29,899
Accounts payable and accrued expenses, total	$ 395,807	$ 380,658

Accrued Professional Liability - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Payables and Accruals [Abstract]
Total accrued professional liability	$ 202,527	$ 168,369	$ 158,691	$ 137,036
Accrued professional liability incurred but loss reserves not reported for claims	142,400	120,600
Accrued professional liability incurred and loss reserves reported for claims	$ 60,100	$ 47,800

Accrued Professional Liability - Schedule of Accrued Professional Liability (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Payables and Accruals [Abstract]
Balance at beginning of year	$ 168,369	$ 158,691	$ 137,036
Assumed liabilities through acquisition	35,968
Provision (adjustment) for losses related to Current year	39,204	39,386	41,235
Provision (adjustment) for losses related to Prior years	(25,797)	(16,125)	(8,100)
Total provision for losses	13,407	23,261	33,135
Claim payments related to Current year	(1,382)	(293)	(741)
Claim payments related to Prior years	(13,835)	(13,290)	(10,739)
Total payments	(15,217)	(13,583)	(11,480)
Balance at end of year	$ 202,527	$ 168,369	$ 158,691

Long-Term Debt and Capital Lease Obligations - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2015	Dec. 08, 2015	Dec. 31, 2014	Oct. 29, 2014
Line of Credit Facility [Line Items]
Line of Credit facility, maturity date		Oct. 29, 2019
Line of Credit facility, estimated increase in borrowings	$ 2,200,000,000
Line of credit description		At the Company’s option, borrowings under the Credit Agreement (other than swingline loans) will bear interest at (i) the Alternate Base Rate (defined as the higher of (a) the prime rate, (b) the Federal Funds Rate plus 1/2 of 1.00% and (c) LIBOR for an interest period of one month plus 1.00%) plus an applicable margin rate ranging from 0.125% to 0.750% based on the Company’s consolidated leverage ratio or (ii) the LIBOR rate plus an applicable margin rate ranging from 1.125% to 1.750% based on the Company’s consolidated leverage ratio. Swingline loans will bear interest at the alternate base rate plus the applicable margin.
Aggregate principal amount of debt		$ 1,283,500,000		$ 568,000,000
Line of Credit facility, reduction in the available balance		200,000
Line of Credit facility, available balance		$ 1,400,000,000
Minimum [Member]
Line of Credit Facility [Line Items]
Commitment fee percentage	0.15%
Maximum [Member]
Line of Credit Facility [Line Items]
Commitment fee percentage	0.30%
Alternate Base Rate [Member]
Line of Credit Facility [Line Items]
Debt instrument, interest rate		1/2 of 1.00%
Alternate Base Rate [Member] \| LIBOR [Member]
Line of Credit Facility [Line Items]
Debt instrument, interest rate		LIBOR for an interest period of one month plus 1.00%
Debt instrument, variable interest rate	1.00%
Applicable Margin Rate [Member] \| LIBOR [Member] \| Minimum [Member]
Line of Credit Facility [Line Items]
Debt instrument, variable interest rate	0.125%
Applicable Margin Rate [Member] \| LIBOR [Member] \| Maximum [Member]
Line of Credit Facility [Line Items]
Debt instrument, variable interest rate	0.75%
Unsecured Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit facility, borrowing capacity	$ 1,700,000,000				$ 1,300,000,000
Term Loan Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit facility, borrowing capacity	200,000,000
Aggregate principal amount of debt		$ 190,000,000		$ 200,000,000
Swingline Loans [Member]
Line of Credit Facility [Line Items]
Line of Credit facility, borrowing capacity	75,000,000
Letter of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit facility, borrowing capacity	$ 37,500,000
5.25% Senior Unsecured Notes Due 2023 [Member]
Line of Credit Facility [Line Items]
Aggregate principal amount of debt		$ 750,000,000	$ 750,000,000
Debt instrument interest rate			5.25%
Debt instrument maturity date description		Payable semi-annually in arrears on June 1 and December 1, beginning on June 1, 2016
Redemption price percentage of principal amount redeemed		100.00%
Redemption price percentage		35.00%
Redemption price percentage of aggregate principal amount redeemed		105.25%
5.25% Senior Unsecured Notes Due 2023 [Member] \| Redemption in 2018 [Member]
Line of Credit Facility [Line Items]
Redemption price percentage of principal amount redeemed		103.938%
5.25% Senior Unsecured Notes Due 2023 [Member] \| Redemption in 2019[Member]
Line of Credit Facility [Line Items]
Redemption price percentage of principal amount redeemed		102.625%
5.25% Senior Unsecured Notes Due 2023 [Member] \| Redemption in 2020 [Member]
Line of Credit Facility [Line Items]
Redemption price percentage of principal amount redeemed		101.313%
5.25% Senior Unsecured Notes Due 2023 [Member] \| Redemption in 2021 and Thereafter [Member]
Line of Credit Facility [Line Items]
Redemption price percentage of principal amount redeemed		100.00%

Long-Term Debt and Capital Lease Obligations - Schedule of Long-Term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 08, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Debt instrument principal amount	$ 1,283,500		$ 568,000
Less: Current portion, principal	(10,000)		(10,000)
Debt instrument principal long-term portion	1,273,500		558,000
Unamortized debt issuance cost	(13,096)		(547)
Less: Current portion, unamortized debt issuance costs	0		0
Long-term portion, principal, unamortized debt issuance costs	(13,096)		(547)
Long term debt	1,270,404		567,453
Less: Current portion	(10,000)		(10,000)
Long-term portion	1,260,404		557,453
Term Loan Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument principal amount	190,000		200,000
Unamortized debt issuance cost	(401)		(547)
Long term debt	189,599		199,453
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument principal amount	343,500		368,000
Long term debt	343,500		$ 368,000
5.25% Senior Unsecured Notes Due 2023 [Member]
Debt Instrument [Line Items]
Debt instrument principal amount	750,000	$ 750,000
Unamortized debt issuance cost	(12,695)
Long term debt	$ 737,305

Long-Term Debt and Capital Lease Obligations - Schedule of Aggregate Annual Maturities of Term Loan and 2023 Senior Notes (Detail) $ in Thousands	Dec. 31, 2015 USD ($)
Long-term Debt, Fiscal Year Maturity [Abstract]
2016	$ 10,000
2017	20,000
2018	30,000
2019	130,000
Thereafter	$ 750,000

Long-Term Debt and Capital Lease Obligations - Schedule of Capital Lease Obligations (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Debt Disclosure [Abstract]
Capital lease obligations	$ 4,299	$ 1,320
Less: Current portion	(1,883)	(465)
Long-term portion	$ 2,416	$ 855

Long-Term Debt and Capital Lease Obligations - Schedule of Amounts Due Under Terms of Capital Lease Obligations (Detail) $ in Thousands	Dec. 31, 2015 USD ($)
Debt Disclosure [Abstract]
2016	$ 1,883
2017	1,632
2018	738
2019	$ 46

Income Taxes - Summary of Components of Income Tax Provision (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Federal, Current									$ 168,596	$ 167,745	$ 134,938
Federal, Deferred									12,866	2,262	14,784
Federal income tax provision, Total									181,462	170,007	149,722
State, Current									20,948	21,109	17,037
State, Deferred									1,628	297	1,136
State income tax provision, Total									22,576	21,406	18,173
Income tax provision, Total	$ 51,581	$ 55,640	$ 52,889	$ 43,928	$ 50,594	$ 51,174	$ 48,944	$ 40,701	$ 204,038	$ 191,413	$ 167,895

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2015	Dec. 31, 2012
Income Tax Contingency [Line Items]
Effective tax rate	37.76%	37.63%	37.44%
Excess tax benefits related to stock-based awards, which increased the cash flow from financing activities	$ 11,600	$ 17,500	$ 19,000
Net operating loss carryforwards for federal and state tax	136,600	29,000	16,900
Company's total liability for uncertain tax positions	18,447	17,165	14,902		$ 13,072
Uncertain tax positions recognized would favorably impact its effective tax rate	17,100
Increase in uncertain tax position	1,200	2,300
Increase in uncertain tax position	2,500
Decrease in uncertain tax position	1,900
Increase (decrease) of interest and penalties	600	300	$ (600)
Company's accrued liability for interest and penalties related to income tax liabilities	$ 9,300	$ 8,700
Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Federal and state income tax examinations	2004
Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Federal and state income tax examinations	2014
Minimum [Member]
Income Tax Contingency [Line Items]
Expiration period of operating loss carryforwards	2019
Uncertain tax positions recognized would favorably impact its effective tax rate				$ 7,000
Decrease in uncertain tax position				7,000
Maximum [Member]
Income Tax Contingency [Line Items]
Expiration period of operating loss carryforwards	2035
Uncertain tax positions recognized would favorably impact its effective tax rate				9,000
Decrease in uncertain tax position				$ 9,000

Income Taxes - Schedule of Differences Between Effective Rate and United States Federal Income Tax Statutory Rate (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Tax at statutory rate	35.00%	35.00%	35.00%
State income tax, net of federal benefit	2.97%	2.74%	2.63%
Non-deductible expenses	0.34%	0.33%	0.27%
Change in accrual estimates relating to uncertain tax positions	(0.43%)	(0.59%)	(0.48%)
Change in valuation allowance	0.29%
Other, net	(0.41%)	0.15%	0.02%
Income tax provision	37.76%	37.63%	37.44%

Income Taxes - Significant Components of Deferred Income Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Components Of Deferred Income Tax Assets And Liabilities [Line Items]
Allowance for uncollectible accounts	$ 82,928	$ 48,178
Reserves and accruals	66,655	62,708
Stock-based compensation	13,662	14,354
Net operating loss carryforward	51,505	10,933
Property and equipment	3,116	1,524
Other	2,723	1,461
Deferred tax assets before valuation allowance	220,589
Less: Valuation allowance	(1,552)
Total deferred tax assets	219,037	139,158
Gross deferred tax liabilities:
Amortization	(311,303)	(214,968)
Accrual to cash adjustment	(55,046)	(38,524)
Other	(6,693)	(192)
Total deferred tax liabilities	(373,042)	(253,684)
Net deferred tax liability	$ (154,005)	(114,526)
Current [Member]
Components Of Deferred Income Tax Assets And Liabilities [Line Items]
Allowance for uncollectible accounts		48,178
Reserves and accruals		26,066
Stock-based compensation		8,346
Net operating loss carryforward		1,504
Other		583
Total deferred tax assets		84,677
Gross deferred tax liabilities:
Accrual to cash adjustment		(38,524)
Other		(192)
Total deferred tax liabilities		(38,716)
Net deferred tax asset		45,961
Non-Current [Member]
Components Of Deferred Income Tax Assets And Liabilities [Line Items]
Reserves and accruals		36,642
Stock-based compensation		6,008
Net operating loss carryforward		9,429
Property and equipment		1,524
Other		878
Total deferred tax assets		54,481
Gross deferred tax liabilities:
Amortization		(214,968)
Total deferred tax liabilities		(214,968)
Net deferred tax liability		$ (160,487)

Income Taxes - Schedule of Activity Related to Gross Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Balance at beginning of year	$ 17,165	$ 14,902	$ 13,072
Increases related to prior year tax positions	467	40	338
Decreases related to prior year tax positions	(1,168)		(38)
Increases related to current year tax positions	3,675	3,750	2,955
Decreases related to lapse of statutes of limitations	(1,692)	(1,527)	(1,425)
Balance at end of year	$ 18,447	$ 17,165	$ 14,902

Common and Common Equivalent Shares - Schedule of Calculation of Shares Used in Basic and Diluted Net Income Per Share (Detail) - shares shares in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Weighted average number of common shares outstanding	92,790	92,949	92,500	94,231	98,066	99,088	98,411	99,076	93,077	98,588	99,112
Weighted average number of dilutive common share equivalents									883	1,299	1,857
Weighted average number of common and common equivalent shares outstanding	93,536	93,646	93,495	95,325	99,129	100,145	99,866	100,696	93,960	99,887	100,969
Antidilutive securities not included in the diluted net income per common share calculation										1	35

Stock Incentive Plans and Stock Purchase Plan - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Nov. 03, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grants and awards under Stock Incentive Plans		5,400,000
Shares issued under Stock Purchase Plan	2,500,000
Stock-based compensation expense related to its stock incentive plans and ESPP		$ 32,100	$ 31,700	$ 31,300
Aggregate fair value of restricted shares, vested		$ 31,600	$ 28,200	$ 33,300
Weighted average grant-date fair value of restricted and deferred stock awards granted		$ 70.44	$ 57.73	$ 46.48
Stock-based compensation cost related to non-vested stock options remaining to be recognized as compensation expense, weighted-average period in years		1 year 6 months
Unrecognized Compensation Expense related to Nonvested Shares		$ 28,700
Aggregate intrinsic value of stock options exercised		11,300	$ 38,800	$ 35,400
Excess tax benefit related to employee stock incentive plans		11,583	17,479	18,981
Cash proceeds received from the exercise of stock options		$ 6,100	$ 30,100	$ 18,900
1996 Non-Qualified Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of market value of common stock at which employees are permitted to purchase	85.00%
Shares issued under Stock Purchase Plan		234,000
Shares reserved for issuance		2,600,000
2015 Non-Qualified Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of market value of common stock at which employees are permitted to purchase	90.00%
Shares reserved for issuance		2,600,000
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of years over which options become exercisable on a pro rata basis		3 years
Stock Option [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of options, maximum years		10 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of years over which options become exercisable on a pro rata basis		3 years

Stock Incentive Plans and Stock Purchase Plan - Schedule of Weighted Average Grant Date Fair Values (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of Shares, Non-vested shares at January 1, 2015	1,271,044
Number of Shares, Awarded	483,423
Number of Shares, Forfeited	(29,974)
Number of Shares, Vested	(710,702)
Number of Shares, Non-vested shares at December 31, 2015	1,013,791	1,271,044
Weighted Average Fair Value, Non-vested shares at January 1, 2015	$ 46.80
Weighted Average Fair Value, Awarded	70.44	$ 57.73	$ 46.48
Weighted Average Fair Value, Forfeited	55.77
Weighted Average Fair Value, Vested	44.43
Weighted Average Fair Value, Non-vested shares at December 31, 2015	$ 61.50	$ 46.80

Stock Incentive Plans and Stock Purchase Plan - Schedule of Activity and Certain Other Information Related to Stock Option Awards (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of Shares, Outstanding at January 1, 2015	814,094
Number of Shares, Exercised	(228,707)
Number of Shares, Outstanding at December 31, 2015	585,387	814,094
Number of Shares, Exercisable at December 31, 2015	585,387
Weighted Average Exercise Price, Outstanding at January 1, 2015	$ 27.57
Weighted Average Exercise Price, Exercised	26.58
Weighted Average Exercise Price, Outstanding at December 31, 2015	27.96	$ 27.57
Weighted Average Exercise Price, Exercisable at December 31, 2015	$ 27.96
Weighted Average Remaining Contractual Term (in years), Outstanding at December 31, 2015	2 years 8 months 12 days
Weighted Average Remaining Contractual Term (in years), Exercisable at December 31, 2015	2 years 8 months 12 days
Aggregate Intrinsic Value, Exercised	$ 11.3	$ 38.8	$ 35.4
Aggregate Intrinsic Value, Outstanding at December 31, 2015	25.6
Aggregate Intrinsic Value, Exercisable at December 31, 2015	$ 25.6

Common Stock Repurchase Programs - Additional Information (Detail) - USD ($)			1 Months Ended		12 Months Ended
	Mar. 16, 2015	Dec. 17, 2014	Oct. 31, 2015	Jul. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2015	Oct. 31, 2014
Common Stock [Line Items]
Common stock authorized for repurchase									$ 600,000,000
Common stock purchase						$ 200,000,000		$ 200,000,000
Common stock repurchased					$ 235,051,000	$ 488,429,000	$ 51,863,000
Common stock shares issued					3,400,000
Number of shares withheld to satisfy minimum statutory tax withholding obligations					710,702
Accelerated Share Repurchase (ASR) Agreements [Member]
Common Stock [Line Items]
Common stock repurchased	$ 200,000,000	$ 200,000,000
Common stock shares issued	2,200,000	2,500,000	300,000	300,000
Amount withheld to satisfy minimum statutory tax withholding obligations					$ 1,500,000
Accelerated Share Repurchase (ASR) Agreements [Member] \| Restricted Stock Units (RSUs) [Member]
Common Stock [Line Items]
Number of shares withheld to satisfy minimum statutory tax withholding obligations					18,282

Commitments and Contingencies - Schedule of Future Minimum Lease Payments under Non-Cancelable Operating Leases (Detail) $ in Thousands	Dec. 31, 2015 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2016	$ 29,856
2017	23,045
2018	17,856
2019	11,691
2020	7,402
Thereafter	11,911
Total	$ 101,761

Selected Quarterly Financial Information - Summary of Company's Selected Quarterly Financial Information (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Net revenue	$ 741,740	$ 722,273	$ 676,588	$ 639,395	$ 650,525	$ 626,506	$ 595,544	$ 566,338	$ 2,779,996	$ 2,438,913	$ 2,154,012
Practice salaries and benefits	461,074	450,033	422,803	419,595	404,345	394,794	372,216	372,040	1,753,505	1,543,395	1,361,318
Practice supplies and other operating expenses	26,164	24,007	24,878	23,431	23,549	21,570	22,466	21,417	98,480	89,002	82,388
General and administrative expenses	85,393	80,185	72,401	67,936	67,641	60,643	60,829	58,414	305,915	247,527	218,209
Depreciation and amortization	18,149	16,918	15,549	13,612	13,903	11,356	10,361	10,370	64,228	45,990	39,966
Total operating expenses	590,780	571,143	535,631	524,574	509,438	488,363	465,872	462,241	2,222,128	1,925,914	1,701,881
Income from operations	150,960	151,130	140,957	114,821	141,087	138,143	129,672	104,097	557,868	512,999	452,131
Investment and other income	751	567	384	142	195	563	335	1,635	1,844	2,728	1,696
Interest expense	(8,493)	(6,201)	(5,149)	(3,267)	(3,313)	(2,019)	(2,188)	(1,371)	(23,110)	(8,891)	(5,415)
Equity in earnings of unconsolidated affiliate	777	784	745	821	905	725	150		3,127	1,780
Total non-operating expenses	(6,965)	(4,850)	(4,020)	(2,304)	(2,213)	(731)	(1,703)	264	(18,139)	(4,383)	(3,719)
Income before income taxes	143,995	146,280	136,937	112,517	138,874	137,412	127,969	104,361	539,729	508,616	448,412
Income tax provision	51,581	55,640	52,889	43,928	50,594	51,174	48,944	40,701	204,038	191,413	167,895
Net income	92,414	90,640	84,048	68,589	88,280	86,238	79,025	63,660	335,691	317,203	280,517
Net (income) loss attributable to noncontrolling interests	288	141	82	118	118	(31)	(9)		629	78
Net income attributable to MEDNAX, Inc.	$ 92,702	$ 90,781	$ 84,130	$ 68,707	$ 88,398	$ 86,207	$ 79,016	$ 63,660	$ 336,320	$ 317,281	$ 280,517
Earnings per share, Basic	$ 1.00	$ 0.98	$ 0.91	$ 0.73	$ 0.90	$ 0.87	$ 0.80	$ 0.64	$ 3.61	$ 3.22	$ 2.83
Earnings per share, Diluted	$ 0.99	$ 0.97	$ 0.90	$ 0.72	$ 0.89	$ 0.86	$ 0.79	$ 0.63	$ 3.58	$ 3.18	$ 2.78
Weighted average shares, Basic	92,790	92,949	92,500	94,231	98,066	99,088	98,411	99,076	93,077	98,588	99,112
Weighted average shares, Diluted	93,536	93,646	93,495	95,325	99,129	100,145	99,866	100,696	93,960	99,887	100,969

General - Additional Information (Detail)	12 Months Ended
General - Additional Information (Detail)	Dec. 31, 2015 Acquisition	Dec. 31, 2014 Acquisition Business
Business Acquisition [Line Items]
Number of complementary business acquired \| Acquisition	12	13
Complementary Business [Member]
Business Acquisition [Line Items]
Number of complementary business acquired \| Business		2

Goodwill and Intangible Assets - Summary of Intangible Assets, Net (Parenthetical) (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense, after year five	$ 229.3	$ 69.1