Acquisitions and Joint Ventures - Schedule of Recognized Identified Assets Acquired and Liabilities Assumed (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($)
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Line Items]
Payments to Acquire Businesses, Gross	$ 71,677
Accounts Receivable Acquired	6,532
Trade Name Acquired	13,953
Certificate of Need/Licenses Acquired	16,447
Finite-lived Intangible Assets Acquired	6
Other Assets and (Liabilities), Net; Acquired (Assumed)	2,121
Fair Value of Assets Acquired	39,059
Acquired noncontrolling interest	52,492
Goodwill, Acquired During Period, Including Noncontrolling Interest of $34,313	85,110
Goodwill related to noncontrolling interests	$ 34,313