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 income	$ 69,014	$ 82,748
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	56,689	54,246
Expenses associated with debt refinancing transactions	1,828
Amortization of debt issuance costs and other non-cash interest	2,224	2,141
Deferred income taxes	2,667	10,606
Income tax benefit of equity compensation	(2,282)	(1,811)
Non-cash equity compensation	5,903	5,231
Other expenses and non-cash items	926	1,234
Changes in assets and liabilities, net:
Accounts receivable, prepaid expenses and other assets	15,008	51,318
Accounts payable, accrued expenses and other liabilities	(23,332)	(17,598)
Income taxes payable	1,367	1,166
Net cash provided by operating activities	130,012	189,281
CASH FLOWS FROM INVESTING ACTIVITIES:
Expenditures for facility development and expansions	(16,843)	(21,872)
Expenditures for other capital improvements	(25,520)	(15,926)
Proceeds from sale of assets	495	198
Increase in other assets	(2,246)	(1,239)
Payments received on direct financing lease	759	672
Net cash used in investing activities	(43,355)	(38,167)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of debt	758,500	80,623
Principal repayments of debt	(813,500)	(133,589)
Payment of debt issuance and other refinancing and related costs	(6,327)
Income tax benefit of equity compensation	2,282	1,811
Purchase and retirement of common stock	(2,481)	(72,589)
Proceeds from exercise of stock options	2,078	1,744
Dividends paid	(19,911)
Net cash used in financing activities	(79,359)	(122,000)
NET INCREASE IN CASH AND CASH EQUIVALENTS	7,298	29,114
CASH AND CASH EQUIVALENTS, beginning of period	55,832	25,509
CASH AND CASH EQUIVALENTS, end of period	63,130	54,623
Cash paid during the period for:
Interest (net of amounts capitalized of $635 and $384 in 2012 and 2011, respectively)	38,606	35,901
Income taxes	$ 38,998	$ 41,461