Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Revenue, Major Customer [Line Items]
Provision for uncollectibles			$ (207,046)	$ (144,514)
Net revenue	$ 758,499	$ 641,950	$ 1,483,177	$ 1,212,395
Ambulatory Services [Member]
Revenue, Major Customer [Line Items]
Percentage of revenues from governmental healthcare programs			26.00%	26.00%
Net revenue	319,747	310,991	$ 626,881	$ 594,901
Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	501,674	365,044	977,161	688,342
Contract and other revenue	38,411	31,698	74,076	62,687
Provision for uncollectibles	(101,333)	(65,783)	(194,941)	(133,535)
Net revenue	438,752	330,959	856,296	617,494
Medicare [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	61,775	45,967	120,549	87,296
Medicaid [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	30,698	19,298	61,523	37,878
Commercial and Managed Care [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	337,553	254,481	661,724	474,599
Self-Pay [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Net fee for service revenue	$ 71,648	$ 45,298	$ 133,365	$ 88,569
Sales Revenue, Net [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	100.00%	100.00%	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%	110.00%	114.00%	111.00%
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%	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%	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	77.00%	77.00%	77.00%	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	16.00%	14.00%	16.00%	14.00%
Contract and Other Revenue [Member] \| Sales Revenue, Net [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	9.00%	10.00%	9.00%	10.00%
Provision for Uncollectibles [Member] \| Sales Revenue, Net [Member] \| Physician Services [Member]
Revenue, Major Customer [Line Items]
Percent of net revenue, over	23.00%	20.00%	23.00%	22.00%

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Percent healthcare revenues governmental programs.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Amount of revenue recognized for providing services to patients, net of provisions for contractual allowances and discounts.

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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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