Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Revenue, Major Customer [Line Items]
Provision for uncollectibles	$ (99,440)	$ (73,999)
Net revenue	$ 724,678	$ 570,445
Ambulatory Services [Member]
Revenue, Major Customer [Line Items]
Percentage of revenues from governmental healthcare programs	26.00%	25.00%
Net revenue	$ 307,134	$ 283,910
Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	475,487	323,298
Contract and other revenue	35,665	30,989
Provision for uncollectibles	(93,608)	(67,752)
Net revenue	417,544	286,535
Medicare [Member] | Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	58,774	41,329
Medicaid [Member] | Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	30,825	18,580
Commercial and Managed Care [Member] | Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	324,171	220,118
Self-Pay [Member] | Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	$ 61,717	$ 43,271
Sales Revenue, Net [Member] | Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	100.00%	100.00%
Health Care Organization, Patient Service Revenue [Member] | Sales Revenue, Net [Member] | Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	114.00%	113.00%
Health Care Organization, Patient Service Revenue [Member] | Sales Revenue, Net [Member] | Medicare [Member] | Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	14.00%	14.00%
Health Care Organization, Patient Service Revenue [Member] | Sales Revenue, Net [Member] | Medicaid [Member] | Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	7.00%	6.00%
Health Care Organization, Patient Service Revenue [Member] | Sales Revenue, Net [Member] | Commercial and Managed Care [Member] | Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	78.00%	77.00%
Health Care Organization, Patient Service Revenue [Member] | Sales Revenue, Net [Member] | Self-Pay [Member] | Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	15.00%	15.00%
Contract and Other Revenue [Member] | Sales Revenue, Net [Member] | Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	9.00%	11.00%
Provision for Uncollectibles [Member] | Sales Revenue, Net [Member] | Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	22.00%	24.00%