Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011	Dec. 31, 2010
Current assets:
Cash and cash equivalents - unrestricted	$ 19,862	$ 44,388	$ 86,968	$ 124,398
Cash and cash equivalents - restricted	1,150	1,150
Trade receivables, less allowance of $647 and $719, respectively	62,975	41,939
Deferred income taxes	6,444	8,641
Other current assets	40,901	48,538
Total current assets	131,332	144,656
Property and equipment, net of accumulated depreciation	2,205,661	2,209,127
Notes receivable, net of current portion	143,849	142,567
Long-term deferred financing costs	14,758	15,947
Other long-term assets	52,693	50,713
Long-term assets of discontinued operations	376	390
Total assets	2,548,669	2,563,400
Current liabilities:
Current portion of long-term debt and capital lease obligations	763	755
Accounts payable and accrued liabilities	153,244	168,975
Current liabilities of discontinued operations	165	186
Total current liabilities	154,172	169,916
Long-term debt and capital lease obligations, net of current portion	1,061,182	1,073,070
Deferred income taxes	110,345	108,219
Other long-term liabilities	169,668	166,209
Long-term liabilities of discontinued operations	451	451
Commitments and Contingencies
Stockholders' equity:
Preferred stock, $.01 par value, 100,000 shares authorized, no shares issued or outstanding
Common stock, $.01 par value, 150,000 shares authorized, 48,902 and 48,428 shares issued and outstanding, respectively	489	484
Additional paid-in capital	931,213	929,904
Treasury stock of 385 shares, at cost	(4,599)	(4,599)
Retained earnings	161,805	155,777
Accumulated other comprehensive loss	(36,057)	(36,031)
Total stockholders' equity	1,052,851	1,045,535
Total liabilities and stockholders' equity	$ 2,548,669	$ 2,563,400