Uncompensated Care (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Health Care Trust Fund [Line Items]
Total uncompensated care	$ 1,894,594	$ 1,768,401	$ 1,453,790
Uncompensated care, percentage	100.00%	100.00%	100.00%
Charity Care
Health Care Trust Fund [Line Items]
Total uncompensated care	$ 761,783	$ 887,136	$ 733,585
Uncompensated care, percentage	40.00%	50.00%	50.00%
Uninsured Discounts
Health Care Trust Fund [Line Items]
Total uncompensated care	$ 1,132,811	$ 881,265	$ 720,205
Uncompensated care, percentage	60.00%	50.00%	50.00%