Information Concerning Guarantor and Non Guarantor Subsidiaries (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Current assets:
Cash and cash equivalents - unrestricted	$ 44,388	$ 124,398	$ 180,029	$ 1,036
Cash and cash equivalents - restricted	1,150	1,150
Trade receivables, net	41,939	31,793
Estimated fair value of derivative assets	0	22
Deferred income taxes	8,641	6,495
Other current assets	48,538	48,992
Intercompany receivables, net		0
Total current assets	144,656	212,850
Property and equipment, net of accumulated depreciation	2,209,127	2,201,445
Notes receivable, net of current portion	142,567	142,651
Long-term deferred financing costs	15,947	12,521
Other long-term assets	50,713	51,065
Long-term assets of discontinued operations	390	401
Total assets	2,563,400	2,620,933
Current liabilities:
Current portion of long-term debt and capital lease obligations	755	58,574
Accounts payable and accrued liabilities	168,975	175,343
Estimated fair value of derivative liabilities	0	12,475
Current liabilities of discontinued operations	186	357
Total current liabilities	169,916	246,749
Long-term debt and capital lease obligations, net of current portion	1,073,070	1,100,641
Deferred income taxes	108,219	101,140
Other long-term liabilities	166,209	142,200
Long-term liabilities of discontinued operations	451	451
Commitments and contingencies
Stockholders' equity:
Preferred stock
Common stock	484	481
Additional paid-in capital	929,904	916,359
Treasury stock of 385 shares, at cost	(4,599)	(4,599)
Retained earnings	155,777	145,600
Accumulated other comprehensive loss	(36,031)	(28,089)
Total stockholders' equity	1,045,535	1,029,752	1,078,684	903,219
Total liabilities and stockholders' equity	2,563,400	2,620,933
Parent Company [Member]
Current assets:
Cash and cash equivalents - unrestricted	37,562	117,913	175,871	(5,724)
Cash and cash equivalents - restricted	1,150	1,150
Estimated fair value of derivative assets		22
Deferred income taxes	1,195	67
Other current assets	2,710	3,364
Intercompany receivables, net	1,745,197	1,744,290
Total current assets	1,787,814	1,866,806
Property and equipment, net of accumulated depreciation	43,733	38,686
Long-term deferred financing costs	15,947	12,521
Other long-term assets	658,167	654,722
Total assets	2,505,661	2,572,735
Current liabilities:
Current portion of long-term debt and capital lease obligations		58,396
Accounts payable and accrued liabilities	17,934	14,622
Estimated fair value of derivative liabilities		12,475
Total current liabilities	17,934	85,493
Long-term debt and capital lease obligations, net of current portion	1,071,426	1,100,335
Deferred income taxes	(36,586)	(26,398)
Other long-term liabilities	82,358	58,559
Commitments and contingencies
Stockholders' equity:
Preferred stock
Common stock	484	481
Additional paid-in capital	929,904	916,359
Treasury stock of 385 shares, at cost	(4,599)	(4,599)
Retained earnings	480,771	470,594
Accumulated other comprehensive loss	(36,031)	(28,089)
Total stockholders' equity	1,370,529	1,354,746
Total liabilities and stockholders' equity	2,505,661	2,572,735
Guarantor Subsidiaries [Member]
Current assets:
Cash and cash equivalents - unrestricted	6,826	6,485	4,158	6,760
Trade receivables, net	41,939	31,793
Deferred income taxes	7,423	5,748
Other current assets	45,954	45,754
Total current assets	102,142	89,780
Property and equipment, net of accumulated depreciation	2,165,394	2,162,759
Notes receivable, net of current portion	142,567	142,651
Other long-term assets	359,297	362,282
Total assets	2,769,400	2,757,472
Current liabilities:
Current portion of long-term debt and capital lease obligations	755	178
Accounts payable and accrued liabilities	151,458	161,142
Intercompany payables, net	1,958,653	1,947,054
Total current liabilities	2,110,866	2,108,374
Long-term debt and capital lease obligations, net of current portion	1,644	306
Deferred income taxes	144,886	127,768
Other long-term liabilities	83,560	83,346
Commitments and contingencies
Stockholders' equity:
Preferred stock
Common stock	2,388	2,388
Additional paid-in capital	1,081,063	1,081,056
Retained earnings	(655,007)	(645,766)
Total stockholders' equity	428,444	437,678
Total liabilities and stockholders' equity	2,769,400	2,757,472
Non-Guarantor Subsidiaries [Member]
Current assets:
Cash and cash equivalents - unrestricted	0	0	0	0
Cash and cash equivalents - restricted	0	0
Trade receivables, net	0	0
Estimated fair value of derivative assets		0
Deferred income taxes	23	680
Intercompany receivables, net	302,368	287,087
Total current assets	302,391	287,767
Property and equipment, net of accumulated depreciation		0
Notes receivable, net of current portion		0
Long-term deferred financing costs		0
Other long-term assets		0
Long-term assets of discontinued operations	390	401
Total assets	302,781	288,168
Current liabilities:
Current portion of long-term debt and capital lease obligations		0
Accounts payable and accrued liabilities		0
Estimated fair value of derivative liabilities		0
Intercompany payables, net	88,912	84,323
Current liabilities of discontinued operations	186	357
Total current liabilities	89,098	84,680
Deferred income taxes	(81)	(230)
Long-term liabilities of discontinued operations	451	451
Commitments and contingencies
Stockholders' equity:
Preferred stock
Common stock	1	1
Additional paid-in capital	(40,127)	(40,120)
Retained earnings	253,439	243,386
Total stockholders' equity	213,313	203,267
Total liabilities and stockholders' equity	302,781	288,168
Consolidation, Eliminations [Member]
Current assets:
Cash and cash equivalents - unrestricted	0	0	0	0
Cash and cash equivalents - restricted	0	0
Trade receivables, net	0	0
Estimated fair value of derivative assets		0
Deferred income taxes		0
Other current assets	(126)	(126)
Intercompany receivables, net	(2,047,565)	(2,031,377)
Total current assets	(2,047,691)	(2,031,503)
Property and equipment, net of accumulated depreciation		0
Notes receivable, net of current portion		0
Long-term deferred financing costs		0
Other long-term assets	(966,751)	(965,939)
Long-term assets of discontinued operations		0
Total assets	(3,014,442)	(2,997,442)
Current liabilities:
Accounts payable and accrued liabilities	(417)	(421)
Intercompany payables, net	(2,047,565)	(2,031,377)
Total current liabilities	(2,047,982)	(2,031,798)
Other long-term liabilities	291	295
Commitments and contingencies
Stockholders' equity:
Preferred stock
Common stock	(2,389)	(2,389)
Additional paid-in capital	(1,040,936)	(1,040,936)
Retained earnings	76,574	77,386
Total stockholders' equity	(966,751)	(965,939)
Total liabilities and stockholders' equity	$ (3,014,442)	$ (2,997,442)