Supplemental Condensed Consolidating Statements of Cash flows (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 591,732	$ 535,006
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	(279,751)	(282,191)
Proceeds received from sale of assets and businesses	37,118	56,194
Acquisition of property and businesses	(1,320)	(25,092)
Costs incurred for purchase and implementation of electronic health records application	(42,353)	(41,854)
Return of deposit on terminated purchase agreement	0	6,500
Net cash used in investing activities	(286,306)	(286,443)
Cash Flows from Financing Activities:
Reduction of long-term debt	(234,231)	(1,127,829)
Additional borrowings	1,500	906,000
Financing costs	0	(8,257)
Repurchase of common shares	(22,186)	(9,676)
Dividends paid	(14,706)	(14,519)
Issuance of common stock	4,096	3,828
Profit distributions to noncontrolling interests	(51,248)	(13,687)
Changes in intercompany balances with affiliates, net	0	0
Net cash provided by (used in) financing activities	(316,775)	(264,140)
Decrease in cash and cash equivalents	(11,349)	(15,577)
Cash and cash equivalents, beginning of period	23,471	41,229
Cash and cash equivalents, end of period	12,122	25,652
Parent
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	9,438	(7,607)
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	0	0
Proceeds received from sale of assets and businesses	0	0
Acquisition of property and businesses	0	0
Costs incurred for purchase and implementation of electronic health records application	0	0
Return of deposit on terminated purchase agreement		6,500
Net cash used in investing activities	0	6,500
Cash Flows from Financing Activities:
Reduction of long-term debt	(226,761)	(1,123,140)
Additional borrowings	1,500	906,000
Financing costs		(8,257)
Repurchase of common shares	(22,186)	(9,676)
Dividends paid	(14,706)	(14,519)
Issuance of common stock	4,096	3,828
Profit distributions to noncontrolling interests	0	0
Changes in intercompany balances with affiliates, net	248,619	246,871
Net cash provided by (used in) financing activities	(9,438)	1,107
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
Guarantors
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	341,031	379,574
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	(202,758)	(236,978)
Proceeds received from sale of assets and businesses	7,552	49,984
Acquisition of property and businesses	(1,320)	(11,476)
Costs incurred for purchase and implementation of electronic health records application	(42,353)	(41,854)
Return of deposit on terminated purchase agreement		0
Net cash used in investing activities	(238,879)	(240,324)
Cash Flows from Financing Activities:
Reduction of long-term debt	(807)	(2,567)
Additional borrowings	0	0
Financing costs		0
Repurchase of common shares	0	0
Dividends paid	0	0
Issuance of common stock	0	0
Profit distributions to noncontrolling interests	0	0
Changes in intercompany balances with affiliates, net	(108,930)	(151,417)
Net cash provided by (used in) financing activities	(109,737)	(153,984)
Decrease in cash and cash equivalents	(7,585)	(14,734)
Cash and cash equivalents, beginning of period	11,949	33,221
Cash and cash equivalents, end of period	4,364	18,487
Non Guarantors
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	241,263	163,039
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	(76,993)	(45,213)
Proceeds received from sale of assets and businesses	29,566	6,210
Acquisition of property and businesses	0	(13,616)
Costs incurred for purchase and implementation of electronic health records application	0	0
Return of deposit on terminated purchase agreement		0
Net cash used in investing activities	(47,427)	(52,619)
Cash Flows from Financing Activities:
Reduction of long-term debt	(6,663)	(2,122)
Additional borrowings	0	0
Financing costs		0
Repurchase of common shares	0	0
Dividends paid	0	0
Issuance of common stock	0	0
Profit distributions to noncontrolling interests	(51,248)	(13,687)
Changes in intercompany balances with affiliates, net	(139,689)	(95,454)
Net cash provided by (used in) financing activities	(197,600)	(111,263)
Decrease in cash and cash equivalents	(3,764)	(843)
Cash and cash equivalents, beginning of period	11,522	8,008
Cash and cash equivalents, end of period	7,758	7,165
Consolidating Adjustments
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	0	0
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	0	0
Proceeds received from sale of assets and businesses	0	0
Acquisition of property and businesses	0	0
Costs incurred for purchase and implementation of electronic health records application	0	0
Return of deposit on terminated purchase agreement		0
Net cash used in investing activities	0	0
Cash Flows from Financing Activities:
Reduction of long-term debt	0	0
Additional borrowings	0	0
Financing costs		0
Repurchase of common shares	0	0
Dividends paid	0	0
Issuance of common stock	0	0
Profit distributions to noncontrolling interests	0	0
Changes in intercompany balances with affiliates, net	0	0
Net cash provided by (used in) financing activities	0	0
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