Guarantor (Cash Flow Statements) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Cash flows from operating activities:
Net cash flows provided by operating activities	$ 248,933	$ 216,112
Cash flows from investing activities:
Acquisition of interests in surgery centers and related transactions	(59,455)	(16,097)
Acquisition of property and equipment	(20,711)	(20,800)
Proceeds from sale of interests in surgery centers	151	0
Other	107	0
Net cash flows used in investing activities	(79,908)	(36,897)
Cash flows from financing activities:
Proceeds from long-term borrowings	129,435	50,211
Repayment on long-term borrowings	(151,676)	(111,139)
Distributions to noncontrolling interests	(137,081)	(123,066)
Net cash flows provided by (used in) financing activities	(169,920)	(184,251)
Net increase (decrease) in cash and cash equivalents	(895)	(5,036)
Cash and cash equivalents, beginning of period	46,398	40,718
Cash and cash equivalents, end of period	45,503	35,682
Consolidation, Eliminations [Member]
Cash flows from operating activities:
Net cash flows provided by operating activities	(247,704)	(295,639)
Cash flows from investing activities:
Acquisition of interests in surgery centers and related transactions	444	68
Acquisition of property and equipment	0	0
Proceeds from sale of interests in surgery centers	0
Other	0	0
Net cash flows used in investing activities	444	68
Cash flows from financing activities:
Proceeds from long-term borrowings	0	0
Repayment on long-term borrowings	0	0
Distributions to noncontrolling interests	247,704	295,639
Changes In Intercompany Balances	0	0
Other financing activities, net	(444)	(68)
Net cash flows provided by (used in) financing activities	247,260	295,571
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents, beginning of period	0	0
Cash and cash equivalents, end of period	0	0
Parent Company [Member]
Cash flows from operating activities:
Net cash flows provided by operating activities	29,083	57,102
Cash flows from investing activities:
Acquisition of interests in surgery centers and related transactions	0	0
Acquisition of property and equipment	(3,264)	(2,233)
Proceeds from sale of interests in surgery centers	0
Other	107	0
Net cash flows used in investing activities	(3,157)	(2,233)
Cash flows from financing activities:
Proceeds from long-term borrowings	122,200	47,700
Repayment on long-term borrowings	(141,403)	(102,700)
Distributions to noncontrolling interests	0	0
Changes In Intercompany Balances	1,899	(1,435)
Other financing activities, net	(11,620)	(2,097)
Net cash flows provided by (used in) financing activities	(28,924)	(58,532)
Net increase (decrease) in cash and cash equivalents	(2,998)	(3,663)
Cash and cash equivalents, beginning of period	7,259	8,530
Cash and cash equivalents, end of period	4,261	4,867
Guarantor Subsidiaries [Member]
Cash flows from operating activities:
Net cash flows provided by operating activities	153,382	155,233
Cash flows from investing activities:
Acquisition of interests in surgery centers and related transactions	(59,899)	(16,165)
Acquisition of property and equipment	0	0
Proceeds from sale of interests in surgery centers	151
Other	0	0
Net cash flows used in investing activities	(59,748)	(16,165)
Cash flows from financing activities:
Proceeds from long-term borrowings	0	0
Repayment on long-term borrowings	0	0
Distributions to noncontrolling interests	(94,322)	(140,406)
Changes In Intercompany Balances	0	0
Other financing activities, net	688	1,338
Net cash flows provided by (used in) financing activities	(93,634)	(139,068)
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents, beginning of period	0	0
Cash and cash equivalents, end of period	0	0
Non-Guarantor Subsidiaries [Member]
Cash flows from operating activities:
Net cash flows provided by operating activities	314,172	299,416
Cash flows from investing activities:
Acquisition of interests in surgery centers and related transactions	0	0
Acquisition of property and equipment	(17,447)	(18,567)
Proceeds from sale of interests in surgery centers	0
Other	0	0
Net cash flows used in investing activities	(17,447)	(18,567)
Cash flows from financing activities:
Proceeds from long-term borrowings	7,235	2,511
Repayment on long-term borrowings	(10,273)	(8,439)
Distributions to noncontrolling interests	(290,463)	(278,299)
Changes In Intercompany Balances	(1,899)	1,435
Other financing activities, net	778	570
Net cash flows provided by (used in) financing activities	(294,622)	(282,222)
Net increase (decrease) in cash and cash equivalents	2,103	(1,373)
Cash and cash equivalents, beginning of period	39,139	32,188
Cash and cash equivalents, end of period	41,242	30,815
Consolidated Entities [Member]
Cash flows from financing activities:
Changes In Intercompany Balances	0	0
Other financing activities, net	$ (10,598)	$ (257)