Supplemental Guarantors Consolidating Condensed Financial Information (Statement of Operations) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Condensed Financial Statements, Captions [Line Items]
REVENUE	$ 51,556	$ 52,208	$ 170,131	$ 147,249
EXPENSES:
Depreciation and amortization	37,703	34,052	106,924	99,712
Cost of sales	104	13	352	68
Selling, general and administrative	4,845	7,637	20,642	23,127
Total operating expenses	42,652	41,702	127,918	122,907
INCOME (LOSS) FROM OPERATIONS	8,904	10,506	42,213	24,342
Interest expense, net	(7,266)	(7,198)	(21,738)	(27,622)
Foreign currency exchange gains (losses)	1,051	(1,631)	1,036	(1,174)
Loss on early extinguishment of debt	0	(7,912)	0	(7,912)
Gain on sale of marketable securities	0	0	230	2,467
Other income	227	44	710	208
Income (loss) before income taxes and equity in income of subsidiaries	2,916	(6,191)	22,451	(9,691)
Provision (benefit) for income taxes	1,787	(1,080)	5,346	(65)
Equity in income of subsidiaries			0	0
NET INCOME (LOSS)	1,129	(5,111)	17,105	(9,626)
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
REVENUE			0	0
EXPENSES:
Depreciation and amortization			0	0
Cost of sales			0	0
Selling, general and administrative			1,601	1,278
Total operating expenses			1,601	1,278
INCOME (LOSS) FROM OPERATIONS			(1,601)	(1,278)
Interest expense, net			(9,690)	(12,047)
Foreign currency exchange gains (losses)			0	0
Loss on early extinguishment of debt				(7,912)
Gain on sale of marketable securities			0	0
Other income			20	3
Income (loss) before income taxes and equity in income of subsidiaries			(11,271)	(21,234)
Provision (benefit) for income taxes			0	0
Equity in income of subsidiaries			28,376	11,608
NET INCOME (LOSS)			17,105	(9,626)
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
REVENUE			106,372	102,973
EXPENSES:
Depreciation and amortization			64,927	64,744
Cost of sales			335	61
Selling, general and administrative			12,313	14,498
Total operating expenses			77,575	79,303
INCOME (LOSS) FROM OPERATIONS			28,797	23,670
Interest expense, net			(10,995)	(14,972)
Foreign currency exchange gains (losses)			(4)	4
Loss on early extinguishment of debt				0
Gain on sale of marketable securities			230	2,467
Other income			690	27
Income (loss) before income taxes and equity in income of subsidiaries			18,718	11,196
Provision (benefit) for income taxes			1,420	(251)
Equity in income of subsidiaries			11,078	161
NET INCOME (LOSS)			28,376	11,608
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
REVENUE			64,730	45,245
EXPENSES:
Depreciation and amortization			41,997	34,968
Cost of sales			17	7
Selling, general and administrative			7,699	8,320
Total operating expenses			49,713	43,295
INCOME (LOSS) FROM OPERATIONS			15,017	1,950
Interest expense, net			(1,053)	(603)
Foreign currency exchange gains (losses)			1,040	(1,178)
Loss on early extinguishment of debt				0
Gain on sale of marketable securities			0	0
Other income			0	178
Income (loss) before income taxes and equity in income of subsidiaries			15,004	347
Provision (benefit) for income taxes			3,926	186
Equity in income of subsidiaries			0	0
NET INCOME (LOSS)			11,078	161
Consolidating Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
REVENUE			(971)	(969)
EXPENSES:
Depreciation and amortization			0	0
Cost of sales			0	0
Selling, general and administrative			(971)	(969)
Total operating expenses			(971)	(969)
INCOME (LOSS) FROM OPERATIONS			0	0
Interest expense, net			0	0
Foreign currency exchange gains (losses)			0	0
Loss on early extinguishment of debt				0
Gain on sale of marketable securities			0	0
Other income			0	0
Income (loss) before income taxes and equity in income of subsidiaries			0	0
Provision (benefit) for income taxes			0	0
Equity in income of subsidiaries			(39,454)	(11,769)
NET INCOME (LOSS)			$ (39,454)	$ (11,769)