Supplemental Condensed Consolidating Statements of Cash flows (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	$ 194,639	$ 178,497
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	(92,387)	(95,919)
Proceeds received from sale of assets and businesses	11,450	6,657
Acquisition of property and businesses	(3,301)	0
Costs incurred for purchase and implementation of electronic health records application	(6,504)	(16,412)
Net cash provided by (used in) investing activities	(90,742)	(105,674)
Cash Flows from Financing Activities:
Reduction of long-term debt	(109,054)	(69,926)
Additional borrowings	11,900	9,500
Repurchase of common shares	(13,993)	(14,027)
Dividends paid	(4,933)	(4,870)
Issuance of common stock	1,445	1,232
Excess income tax benefits related to stock-based compensation	11,750	9,266
Profit distributions to noncontrolling interests	(1,989)	(10,074)
Changes in intercompany balances with affiliates, net	0	0
Net cash (used in) provided by financing activities	(104,874)	(78,899)
Decrease in cash and cash equivalents	(977)	(6,076)
Cash and cash equivalents, beginning of period	17,238	23,471
Cash and cash equivalents, end of period	16,261	17,395
Parent
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	70,888	64,747
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
Net cash provided by (used in) investing activities	0	0
Cash Flows from Financing Activities:
Reduction of long-term debt	(97,975)	(63,612)
Additional borrowings	11,900	9,500
Repurchase of common shares	(13,993)	(14,027)
Dividends paid	(4,933)	(4,870)
Issuance of common stock	1,445	1,232
Excess income tax benefits related to stock-based compensation	11,750	9,266
Profit distributions to noncontrolling interests	0	0
Changes in intercompany balances with affiliates, net	20,918	(2,236)
Net cash (used in) provided by financing activities	(70,888)	(64,747)
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 (used in) provided by operating activities	51,661	35,367
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	(70,385)	(54,822)
Proceeds received from sale of assets and businesses	11,450	4,178
Acquisition of property and businesses	0	0
Costs incurred for purchase and implementation of electronic health records application	(6,504)	(16,412)
Net cash provided by (used in) investing activities	(65,439)	(67,056)
Cash Flows from Financing Activities:
Reduction of long-term debt	(228)	(265)
Additional borrowings	0	0
Repurchase of common shares	0	0
Dividends paid	0	0
Issuance of common stock	0	0
Excess income tax benefits related to stock-based compensation	0	0
Profit distributions to noncontrolling interests	0	0
Changes in intercompany balances with affiliates, net	13,735	28,322
Net cash (used in) provided by financing activities	13,507	28,057
Decrease in cash and cash equivalents	(271)	(3,632)
Cash and cash equivalents, beginning of period	7,990	11,949
Cash and cash equivalents, end of period	7,719	8,317
Non Guarantors
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	72,090	78,383
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	(22,002)	(41,097)
Proceeds received from sale of assets and businesses	0	2,479
Acquisition of property and businesses	(3,301)	0
Costs incurred for purchase and implementation of electronic health records application	0	0
Net cash provided by (used in) investing activities	(25,303)	(38,618)
Cash Flows from Financing Activities:
Reduction of long-term debt	(10,851)	(6,049)
Additional borrowings	0	0
Repurchase of common shares	0	0
Dividends paid	0	0
Issuance of common stock	0	0
Excess income tax benefits related to stock-based compensation	0	0
Profit distributions to noncontrolling interests	(1,989)	(10,074)
Changes in intercompany balances with affiliates, net	(34,653)	(26,086)
Net cash (used in) provided by financing activities	(47,493)	(42,209)
Decrease in cash and cash equivalents	(706)	(2,444)
Cash and cash equivalents, beginning of period	9,248	11,522
Cash and cash equivalents, end of period	8,542	9,078
Consolidating Adjustments
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by 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
Costs incurred for purchase and implementation of electronic health records application	0	0
Net cash provided by (used in) investing activities	0	0
Cash Flows from Financing Activities:
Reduction of long-term debt	0	0
Additional borrowings	0	0
Repurchase of common shares	0	0
Dividends paid	0	0
Issuance of common stock	0	0
Excess income tax benefits related to stock-based compensation	0	0
Profit distributions to noncontrolling interests	0	0
Changes in intercompany balances with affiliates, net	0	0
Net cash (used in) provided by 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