Acquisitions and Joint Ventures - Schedule of Recognized Identified Assets Acquired and Liabilities Assumed (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($)
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Line Items]
Payments to Acquire Businesses, Gross	$ 33,134
Accounts Receivable Acquired	5,143
Trade Name Acquired	6,159
Certificate of Need/Licenses Acquired	7,962
Finite-lived Intangible Assets Acquired	6
Other Assets and (Liabilities), Net; Acquired (Assumed)	(1,084)
Fair Value of Assets Acquired	18,186
Acquired noncontrolling interest	22,572
Goodwill, Acquired During Period, Including Noncontrolling Interest of $14,213	37,520
Goodwill related to noncontrolling interests	$ 14,213