Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash Flows from Operating Activities:
Net income	$ 448,870	$ 275,795	$ 304,247
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation & amortization	295,861	223,997	204,703
Gains on sales of assets and businesses, net of losses	(452)	(1,993)	(1,346)
Stock based compensation expense	18,225	16,799	13,096
Changes in assets & liabilities, net of effects from acquisitions and dispositions:
Accounts receivable	(134,838)	22,726	(1,402)
Construction management and other receivable			29,519
Accrued interest	(3,577)	8,408	357
Accrued and deferred income taxes	85,792	132	14,930
Other working capital accounts	(28,382)	(26,437)	(18,828)
Other assets and deferred charges	37,160	11,539	6,699
Other	(1,387)	812	755
Accrued insurance expense, net of commercial premiums paid	83,612	19,739	44,314
Payments made in settlement of self-insurance claims	(82,633)	(50,173)	(55,782)
Net cash provided by operating activities	718,251	501,344	541,262
Cash Flows from Investing Activities:
Property and equipment additions, net of disposals	(285,682)	(239,274)	(379,748)
Acquisition of property and businesses	(29,466)	(1,958,298)	(12,499)
Proceeds received from sales of assets and businesses	67,592	21,460	9,770
Costs incurred for purchase and implementation of electronic health records application	(38,249)	(17,971)	(7,957)
Net cash used in investing activities	(285,805)	(2,194,083)	(390,434)
Cash Flows from Financing Activities:
Reduction of long-term debt	(381,517)	(1,392,086)	(66,499)
Additional borrowings	98,100	3,266,146	26,069
Financing costs	(23,608)	(101,815)
Repurchase of common shares	(60,482)	(11,528)	(63,288)
Dividends paid	(19,466)	(19,422)	(16,706)
Issuance of common stock	4,779	3,594	3,290
Profit distributions to noncontrolling interests	(38,497)	(32,456)	(29,866)
Proceeds from sale of noncontrolling interests in majority owned business		600
Capital contributions from noncontrolling interests			121
Purchase of noncontrolling interests in majority owned businesses		(600)	(229)
Net cash (used in) provided by financing activities	(420,691)	1,713,033	(147,108)
Increase in cash and cash equivalents	11,755	20,294	3,720
Cash and cash equivalents, beginning of period	29,474	9,180	5,460
Cash and cash equivalents, end of period	41,229	29,474	9,180
Supplemental Disclosures of Cash Flow Information:
Interest paid	176,328	76,900	57,018
Income taxes paid, net of refunds	$ 163,029	$ 152,088	$ 155,368