Goodwill and Intangible Assets - Summary of Intangible Assets, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 871,821	$ 567,195
Accumulated Amortization	(203,292)	(142,976)
Net Carrying Value	668,529	424,219
Physician And Hospital Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	347,862	265,465
Accumulated Amortization	(168,488)	(130,050)
Net Carrying Value	179,374	135,415
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	443,300	248,880
Accumulated Amortization	(27,368)	(10,612)
Net Carrying Value	415,932	238,268
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	43,156	28,620
Accumulated Amortization	(1,604)	(597)
Net Carrying Value	41,552	28,023
Patented and Other Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	37,503	24,230
Accumulated Amortization	(5,832)	(1,717)
Net Carrying Value	$ 31,671	$ 22,513

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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