Uncompensated Care (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Health Care Trust Fund [Line Items]
Total uncompensated care	$ 1,453,790	$ 1,203,034	$ 1,136,022
Uncompensated care, percentage	100.00%	100.00%	100.00%
Charity Care
Health Care Trust Fund [Line Items]
Total uncompensated care	$ 733,585	$ 506,571	$ 515,435
Uncompensated care, percentage	50.00%	42.00%	45.00%
Uninsured Discounts
Health Care Trust Fund [Line Items]
Total uncompensated care	$ 720,205	$ 696,463	$ 620,587
Uncompensated care, percentage	50.00%	58.00%	55.00%