Estimated Cost of Providing Uncompensated Care (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Health Care Trust Fund [Line Items]
Estimated cost of providing uncompensated care	$ 184,187	$ 172,959	$ 161,013
Charity Care
Health Care Trust Fund [Line Items]
Estimated cost of providing uncompensated care	77,557	78,475	95,675
Uninsured Discounts
Health Care Trust Fund [Line Items]
Estimated cost of providing uncompensated care	$ 106,630	$ 94,484	$ 65,338