Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011
Cash flows from operating activities:
Net earnings (loss)	$ 110,484	$ 91,005
Adjustments to reconcile net earnings to net cash flows provided by operating activities:
Depreciation and amortization	14,838	12,046
Net (gain) loss on sale of long-lived assets	599	(363)
Share-based compensation	3,412	3,171
Excess tax benefit from share-based compensation	(529)	(463)
Deferred income taxes	13,388	11,460
Equity in earnings of unconsolidated affiliates, net	(711)	0
Increase (decrease) in cash and cash equivalents, net of effects of acquisitions and dispositions, due to changes in:
Accounts receivable, net	2,935	(1,534)
Supplies inventory	333	67
Prepaid and other current assets	(331)	2,506
Accounts payable	901	(3,737)
Accrued expenses and other liabilities	(2,616)	(1,866)
Other, net	921	733
Net cash flows provided by (used in) operating activities	143,624	113,025
Cash flows from investing activities:
Acquisition of interests in surgery centers and related transactions	(9,972)	(45,674)
Acquisition of property and equipment	(14,569)	(10,303)
Proceeds from sale of interests in surgery centers	0	3,369
Net cash flows provided by (used in) investing activities	(24,541)	(52,608)
Cash flows from financing activities:
Proceeds from long-term borrowings	33,378	72,984
Repayment on long-term borrowings	(72,517)	(64,852)
Distributions to noncontrolling interests	(82,759)	(67,360)
Distributions received from unconsolidated affiliates	400	0
Proceeds from issuance of common stock upon exercise of stock options	6,672	4,628
Repurchase of common stock	(7,219)	(6,185)
Capital contributions and ownership transactions by noncontrolling interests	1,119	698
Excess tax benefit from share-based compensation	529	463
Financing cost incurred	(1,755)	(1,986)
Net cash flows provided by (used in) financing activities	(122,152)	(61,610)
Net increase (decrease) in cash and cash equivalents	(3,069)	(1,193)
Cash and cash equivalents, beginning of period	40,718	34,147
Cash and cash equivalents, end of period	$ 37,649	$ 32,954

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).