Supplemental Condensed Consolidating Statements of Cash flows (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 815,271	$ 718,251	$ 501,344
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	(363,192)	(285,682)	(239,274)
Acquisition of property and businesses	(527,847)	(29,466)	(1,958,298)
Proceeds received from sale of assets and businesses	149,311	67,592	21,460
Costs incurred for purchase and development of electronic health records application	(54,362)	(38,249)	(17,971)
Return of deposit on terminated purchase agreement	6,500	0	0
Net cash provided by (used in) investing activities	(789,590)	(285,805)	(2,194,083)
Cash Flows from Financing Activities:
Reduction of long-term debt	(849,647)	(381,517)	(1,392,086)
Additional borrowings	913,500	98,100	3,266,146
Financing costs	(8,283)	(23,608)	(101,815)
Repurchase of common shares	(19,154)	(60,482)	(11,528)
Dividends paid	(58,395)	(19,466)	(19,422)
Issuance of common stock	5,435	4,779	3,594
Profit distributions to noncontrolling interests	(26,895)	(38,497)	(32,456)
Proceeds from sale of noncontrolling interest in majority owned business	0	0	600
Changes in intercompany balances with affiliates, net	0	0	0
Net cash (used in) provided by financing activities	(43,439)	(420,691)	1,713,033
Increase (decrease) in cash and cash equivalents	(17,758)	11,755	20,294
Cash and cash equivalents, beginning of period	41,229	29,474	9,180
Cash and cash equivalents, end of period	23,471	41,229	29,474
Parent
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(21,608)	(4,990)	(139,226)
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	0	0	0
Acquisition of property and businesses	0	0	0
Proceeds received from sale of assets and businesses	0	0	0
Costs incurred for purchase and development of electronic health records application	0	0	0
Return of deposit on terminated purchase agreement	6,500
Net cash provided by (used in) investing activities	6,500	0	0
Cash Flows from Financing Activities:
Reduction of long-term debt	(843,002)	(382,060)	(1,388,679)
Additional borrowings	913,500	98,100	3,266,146
Financing costs	(8,283)	(23,608)	(101,815)
Repurchase of common shares	(19,154)	(60,482)	(11,528)
Dividends paid	(58,395)	(19,466)	(19,422)
Issuance of common stock	5,435	4,779	3,594
Profit distributions to noncontrolling interests	0	0	0
Proceeds from sale of noncontrolling interest in majority owned business			0
Changes in intercompany balances with affiliates, net	25,007	387,727	(1,609,070)
Net cash (used in) provided by financing activities	15,108	4,990	139,226
Increase (decrease) in cash and cash equivalents	0	0	0
Cash and cash equivalents, beginning of period	0	0	0
Cash and cash equivalents, end of period	0	0	0
Guarantors
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	594,606	518,462	342,633
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	(312,190)	(226,848)	(186,967)
Acquisition of property and businesses	(513,596)	0	(1,958,904)
Proceeds received from sale of assets and businesses	142,667	0	21,460
Costs incurred for purchase and development of electronic health records application	(54,362)	(38,249)	(17,971)
Return of deposit on terminated purchase agreement	0
Net cash provided by (used in) investing activities	(737,481)	(265,097)	(2,142,382)
Cash Flows from Financing Activities:
Reduction of long-term debt	0	(1,442)	(753)
Additional borrowings	1,613	0	0
Financing costs	0	0	0
Repurchase of common shares	0	0	0
Dividends paid	0	0	0
Issuance of common stock	0	0	0
Profit distributions to noncontrolling interests	0	0	0
Proceeds from sale of noncontrolling interest in majority owned business			0
Changes in intercompany balances with affiliates, net	119,990	(240,087)	1,816,520
Net cash (used in) provided by financing activities	121,603	(241,529)	1,815,767
Increase (decrease) in cash and cash equivalents	(21,272)	11,836	16,018
Cash and cash equivalents, beginning of period	33,221	21,385	5,367
Cash and cash equivalents, end of period	11,949	33,221	21,385
Non Guarantors
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	242,273	204,779	297,937
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	(51,002)	(58,834)	(52,307)
Acquisition of property and businesses	(14,251)	(29,466)	606
Proceeds received from sale of assets and businesses	6,644	67,592	0
Costs incurred for purchase and development of electronic health records application	0	0	0
Return of deposit on terminated purchase agreement	0
Net cash provided by (used in) investing activities	(58,609)	(20,708)	(51,701)
Cash Flows from Financing Activities:
Reduction of long-term debt	(8,258)	0	(2,654)
Additional borrowings	0	1,985	0
Financing costs	0	0	0
Repurchase of common shares	0	0	0
Dividends paid	0	0	0
Issuance of common stock	0	0	0
Profit distributions to noncontrolling interests	(26,895)	(38,497)	(32,456)
Proceeds from sale of noncontrolling interest in majority owned business			600
Changes in intercompany balances with affiliates, net	(144,997)	(147,640)	(207,450)
Net cash (used in) provided by financing activities	(180,150)	(184,152)	(241,960)
Increase (decrease) in cash and cash equivalents	3,514	(81)	4,276
Cash and cash equivalents, beginning of period	8,008	8,089	3,813
Cash and cash equivalents, end of period	11,522	8,008	8,089
Consolidating Adjustments
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	0	0	0
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	0	0	0
Acquisition of property and businesses	0	0	0
Proceeds received from sale of assets and businesses	0	0	0
Costs incurred for purchase and development of electronic health records application	0	0	0
Return of deposit on terminated purchase agreement	0
Net cash provided by (used in) investing activities	0	0	0
Cash Flows from Financing Activities:
Reduction of long-term debt	1,613	1,985	0
Additional borrowings	(1,613)	(1,985)	0
Financing costs	0	0	0
Repurchase of common shares	0	0	0
Dividends paid	0	0	0
Issuance of common stock	0	0	0
Profit distributions to noncontrolling interests	0	0	0
Proceeds from sale of noncontrolling interest in majority owned business			0
Changes in intercompany balances with affiliates, net	0	0	0
Net cash (used in) provided by financing activities	0	0	0
Increase (decrease) in cash and cash equivalents	0	0	0
Cash and cash equivalents, beginning of period	0	0	0
Cash and cash equivalents, end of period	$ 0	$ 0	$ 0