Accounts Receivable and Net Revenue - Schedule of Net Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Abstract]
Net revenue	$ 460,635	$ 454,913	$ 1,317,321	$ 1,321,159
Net patient service revenue [Member]
Disaggregation of Revenue [Abstract]
Net revenue	382,936	400,330	1,133,313	1,159,363
Hospital contract administrative fees [Member]
Disaggregation of Revenue [Abstract]
Net revenue	61,186	51,149	154,840	149,407
Other revenue [Member]
Disaggregation of Revenue [Abstract]
Net revenue	$ 16,513	$ 3,434	$ 29,168	$ 12,389