Information Concerning Guarantor and Non-Guarantor Subsidiaries (Details 1) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2011	Dec. 31, 2010
Current assets:
Cash and cash equivalents - unrestricted	$ 29,504	$ 44,388	$ 111,363	$ 124,398
Cash and cash equivalents - restricted	1,150	1,150
Trade receivables, net	54,194	41,939
Deferred income taxes	4,993	8,641
Other current assets	44,397	48,538
Total current assets	134,238	144,656
Property and equipment, net of accumulated depreciation	2,200,616	2,209,127
Notes receivable, net of current portion	145,271	142,567
Long-term deferred financing costs	13,602	15,947
Other long-term assets	52,285	50,713
Long-term assets of discontinued operations	335	390
Total assets	2,546,347	2,563,400
Current liabilities:
Current portion of long-term debt and capital lease obligations	750	755
Accounts payable and accrued liabilities	151,735	168,975
Current liabilities of discontinued operations	147	186
Total current liabilities	152,632	169,916
Long-term debt and capital lease obligations, net of current portion	1,034,456	1,073,070
Deferred income taxes	119,817	108,219
Other long-term liabilities	170,779	166,209
Long-term liabilities of discontinued operations	451	451
Commitments and Contingencies
Stockholders' equity:
Preferred stock
Common stock	491	484
Additional paid-in capital	937,592	929,904
Treasury stock	(4,599)	(4,599)
Retained earnings	170,759	155,777
Accumulated other comprehensive loss	(36,031)	(36,031)
Total stockholders' equity	1,068,212	1,045,535
Total liabilities and stockholders' equity	2,546,347	2,563,400
Issuer [Member]
Current assets:
Cash and cash equivalents - unrestricted	25,844	37,562	107,310	117,913
Cash and cash equivalents - restricted	1,150	1,150
Deferred income taxes	88	1,195
Other current assets	1,746	2,710
Intercompany receivables, net	1,730,974	1,745,197
Total current assets	1,759,802	1,787,814
Property and equipment, net of accumulated depreciation	48,481	43,733
Long-term deferred financing costs	13,602	15,947
Other long-term assets	668,174	658,167
Total assets	2,490,059	2,505,661
Current liabilities:
Accounts payable and accrued liabilities	8,791	17,934
Total current liabilities	8,791	17,934
Long-term debt and capital lease obligations, net of current portion	1,033,180	1,071,426
Deferred income taxes	(29,598)	(36,586)
Other long-term liabilities	84,480	82,358
Commitments and Contingencies
Stockholders' equity:
Preferred stock
Common stock	491	484
Additional paid-in capital	937,592	929,904
Treasury stock	(4,599)	(4,599)
Retained earnings	495,753	480,771
Accumulated other comprehensive loss	(36,031)	(36,031)
Total stockholders' equity	1,393,206	1,370,529
Total liabilities and stockholders' equity	2,490,059	2,505,661
Guarantor [Member]
Current assets:
Cash and cash equivalents - unrestricted	3,660	6,826	4,053	6,485
Trade receivables, net	54,194	41,939
Deferred income taxes	4,882	7,423
Other current assets	42,777	45,954
Total current assets	105,513	102,142
Property and equipment, net of accumulated depreciation	2,152,135	2,165,394
Notes receivable, net of current portion	145,271	142,567
Other long-term assets	358,460	359,297
Total assets	2,761,379	2,769,400
Current liabilities:
Current portion of long-term debt and capital lease obligations	750	755
Accounts payable and accrued liabilities	143,361	151,458
Intercompany payables, net	1,948,379	1,958,653
Total current liabilities	2,092,490	2,110,866
Long-term debt and capital lease obligations, net of current portion	1,276	1,644
Deferred income taxes	149,496	144,886
Other long-term liabilities	86,008	83,560
Commitments and Contingencies
Stockholders' equity:
Preferred stock
Common stock	2,388	2,388
Additional paid-in capital	1,081,067	1,081,063
Retained earnings	(651,346)	(655,007)
Total stockholders' equity	432,109	428,444
Total liabilities and stockholders' equity	2,761,379	2,769,400
Non-Guarantor [Member]
Current assets:
Deferred income taxes	23	23
Intercompany receivables, net	310,422	302,368
Total current assets	310,445	302,391
Long-term assets of discontinued operations	335	390
Total assets	310,780	302,781
Current liabilities:
Intercompany payables, net	93,017	88,912
Current liabilities of discontinued operations	147	186
Total current liabilities	93,164	89,098
Deferred income taxes	(81)	(81)
Long-term liabilities of discontinued operations	451	451
Commitments and Contingencies
Stockholders' equity:
Preferred stock
Common stock	1	1
Additional paid-in capital	(40,129)	(40,127)
Retained earnings	257,374	253,439
Total stockholders' equity	217,246	213,313
Total liabilities and stockholders' equity	310,780	302,781
Eliminations [Member]
Current assets:
Cash and cash equivalents - unrestricted
Other current assets	(126)	(126)
Intercompany receivables, net	(2,041,396)	(2,047,565)
Total current assets	(2,041,522)	(2,047,691)
Other long-term assets	(974,349)	(966,751)
Total assets	(3,015,871)	(3,014,442)
Current liabilities:
Accounts payable and accrued liabilities	(417)	(417)
Intercompany payables, net	(2,041,396)	(2,047,565)
Total current liabilities	(2,041,813)	(2,047,982)
Other long-term liabilities	291	291
Commitments and Contingencies
Stockholders' equity:
Preferred stock
Common stock	(2,389)	(2,389)
Additional paid-in capital	(1,040,938)	(1,040,936)
Retained earnings	68,978	76,574
Total stockholders' equity	(974,349)	(966,751)
Total liabilities and stockholders' equity	$ (3,015,871)	$ (3,014,442)