Supplemental Condensed Consolidating Statements of Cash flows (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	$ 884,241	$ 799,231	$ 710,683
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	(358,493)	(363,192)	(285,682)
Acquisition of property and businesses	(12,636)	(527,847)	(29,466)
Proceeds received from sale of assets and businesses	37,482	149,311	67,592
Costs incurred for purchase and development of electronic health records application	(49,811)	(54,362)	(38,249)
Return of deposit on terminated purchase agreement	0	6,500	0
Net cash provided by (used in) investing activities	(383,458)	(789,590)	(285,805)
Cash Flows from Financing Activities:
Reduction of long-term debt	(440,224)	(849,647)	(381,517)
Additional borrowings	15,761	913,500	98,100
Financing costs	(231)	(8,283)	(23,608)
Repurchase of common shares	(27,201)	(19,154)	(60,482)
Dividends paid	(19,621)	(58,395)	(19,466)
Issuance of common stock	5,708	5,435	4,779
Excess income tax benefits related to stock based compensation	20,121	16,040	7,568
Profit distributions to noncontrolling interests	(61,329)	(26,895)	(38,497)
Changes in intercompany balances with affiliates, net	0	0	0
Net cash (used in) provided by financing activities	(507,016)	(27,399)	(413,123)
Increase (decrease) in cash and cash equivalents	(6,233)	(17,758)	11,755
Cash and cash equivalents, beginning of period	23,471	41,229	29,474
Cash and cash equivalents, end of period	17,238	23,471	41,229
Parent
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	17,946	(37,648)	(12,558)
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	0	6,500	0
Cash Flows from Financing Activities:
Reduction of long-term debt	(429,996)	(843,002)	(382,060)
Additional borrowings	15,761	913,500	98,100
Financing costs	(231)	(8,283)	(23,608)
Repurchase of common shares	(27,201)	(19,154)	(60,482)
Dividends paid	(19,621)	(58,395)	(19,466)
Issuance of common stock	5,708	5,435	4,779
Excess income tax benefits related to stock based compensation	20,121	16,040	7,568
Profit distributions to noncontrolling interests	0	0	0
Changes in intercompany balances with affiliates, net	417,513	25,007	387,727
Net cash (used in) provided by financing activities	(17,946)	31,148	12,558
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 (used in) provided by operating activities	587,083	594,606	518,462
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	(269,419)	(312,190)	(226,848)
Acquisition of property and businesses	(8,094)	(513,596)	0
Proceeds received from sale of assets and businesses	7,916	142,667	0
Costs incurred for purchase and development of electronic health records application	(49,811)	(54,362)	(38,249)
Return of deposit on terminated purchase agreement		0
Net cash provided by (used in) investing activities	(319,408)	(737,481)	(265,097)
Cash Flows from Financing Activities:
Reduction of long-term debt	(109)	0	(1,442)
Additional borrowings	0	1,613	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
Excess income tax benefits related to stock based compensation	0	0	0
Profit distributions to noncontrolling interests	0	0	0
Changes in intercompany balances with affiliates, net	(271,525)	119,990	(240,087)
Net cash (used in) provided by financing activities	(271,634)	121,603	(241,529)
Increase (decrease) in cash and cash equivalents	(3,959)	(21,272)	11,836
Cash and cash equivalents, beginning of period	11,949	33,221	21,385
Cash and cash equivalents, end of period	7,990	11,949	33,221
Non Guarantors
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	279,212	242,273	204,779
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	(89,074)	(51,002)	(58,834)
Acquisition of property and businesses	(4,542)	(14,251)	(29,466)
Proceeds received from sale of assets and businesses	29,566	6,644	67,592
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	(64,050)	(58,609)	(20,708)
Cash Flows from Financing Activities:
Reduction of long-term debt	(10,119)	(8,258)	0
Additional borrowings	0	0	1,985
Financing costs	0	0	0
Repurchase of common shares	0	0	0
Dividends paid	0	0	0
Issuance of common stock	0	0	0
Excess income tax benefits related to stock based compensation	0	0	0
Profit distributions to noncontrolling interests	(61,329)	(26,895)	(38,497)
Changes in intercompany balances with affiliates, net	(145,988)	(144,997)	(147,640)
Net cash (used in) provided by financing activities	(217,436)	(180,150)	(184,152)
Increase (decrease) in cash and cash equivalents	(2,274)	3,514	(81)
Cash and cash equivalents, beginning of period	11,522	8,008	8,089
Cash and cash equivalents, end of period	9,248	11,522	8,008
Consolidating Adjustments
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by 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	0	1,613	1,985
Additional borrowings	0	(1,613)	(1,985)
Financing costs	0	0	0
Repurchase of common shares	0	0	0
Dividends paid	0	0	0
Issuance of common stock	0	0	0
Excess income tax benefits related to stock based compensation	0	0	0
Profit distributions to noncontrolling interests	0	0	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