Acquisitions (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended				12 Months Ended		0 Months Ended			0 Months Ended						6 Months Ended			3 Months Ended	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014 Controlling Interest [Member] center	Sep. 30, 2013 Controlling Interest [Member] center	Dec. 31, 2011 National Surgical Care, Inc. [Member] center	Sep. 30, 2013 National Surgical Care, Inc. [Member]	Jul. 16, 2014 Sheridan Healthcare [Member]	Sep. 30, 2014 Sheridan Healthcare [Member]	Jul. 16, 2014 Sheridan Healthcare [Member]	Jul. 16, 2014 Common Stock [Member]	Jul. 02, 2014 Common Stock [Member]	Jul. 16, 2014 Common Stock [Member] Sheridan Healthcare [Member]	Jul. 16, 2014 Mandatory Convertible Preferred Stock [Member]	Jul. 02, 2014 Mandatory Convertible Preferred Stock [Member]	Jul. 16, 2014 Senior Secured Credit Facility - Term Loan [Member]	Jul. 15, 2014 Revolving Credit Facility [Member]	Jul. 16, 2014 Revolving Credit Facility [Member]	Jul. 16, 2014 Senior Notes [Member] 2022 Senior Unsecured Notes [Member]	Sep. 30, 2014 Bridge Loan [Member] Interest Expense [Member] Sheridan Healthcare [Member]	Sep. 30, 2014 Ambulatory Services [Member]	Sep. 30, 2013 Ambulatory Services [Member]
Business Acquisition [Line Items]
Cash paid to acquire business									$ 2,100,000,000
Shares of common stock issued for acquisition														5,713,909
Value of common stock issued for acquisition											272,000,000
Issuance of common stock (in shares)													9,775,000			1,725,000
Proceeds from common stock offering			439,875,000	0								421,000,000
Proceeds from preferred stock offering			172,500,000	0											166,400,000
Maximum borrowing capacity																	870,000,000.0	475,000,000.0	300,000,000.0
Face amount																				1,100,000,000.0
Interest rate																				5.625%
Fees and expenses associated with acquisition										135,700,000
Deferred financing costs										52,900,000
Payments of equity issuance costs			(24,366,000)	0
Transaction costs	25,102,000	110,000	28,681,000	285,000
Fees paid to obtain a commitment for financing																					12,800,000
Debt extinguishment costs	(16,887,000)	0	(16,887,000)	0														(4,500,000)
Number of business acquisitions					2	4	17
Acquisitions and related expenses, net			2,138,648,000	59,455,000																		24,400,000	59,500,000
Final settlement of contingent earn out fee								$ 2,700,000