Income Taxes (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Operating Loss Carryforwards [Line Items]
Excess tax benefit from stock option deductions	$ 8,900,000								$ 8,900,000
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest [Abstract]
Income (loss) from continuing operations before income taxes									32,531,000	(52,534,000)	(63,335,000)
Income tax (benefit) expense allocated to continuing operations									2,300,000	(11,700,000)	(300,000)
Income (loss) from continuing operations	17,689,000	11,778,000	(5,193,000)	5,921,000	(3,560,000)	923,000	(40,706,000)	2,500,000	30,196,000	(40,841,000)	(63,051,000)
Income (loss) from discontinued operations before income taxes									(32,900,000)	27,100,000	(192,300,000)
Income tax benefit (expense) allocated to discontinued operations									200,000	(9,700,000)	(3,000,000)
Income (loss) from discontinued operations	7,279,000	(12,569,000)	(23,885,000)	(3,540,000)	(6,522,000)	(1,689,000)	(8,607,000)	34,243,000	(32,735,000)	17,422,000	(195,251,000)
Net loss	24,968,000	(790,000)	(29,077,000)	2,361,000	(10,082,000)	(766,000)	(49,313,000)	36,743,000	(2,539,000)	(23,419,000)	(258,302,000)
Income tax benefit allocated to additional paid in capital									0	0	0
Income tax benefit (expense) allocated to other comprehensive income									200,000	0	0
Alternative minimum tax	3,100,000								3,100,000
General business credit	14,700,000								14,700,000
Foreign tax credit	10,400,000								10,400,000
Operating loss carryforwards, period									20 years
Domestic Country [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	230,000,000								230,000,000
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 241,200,000								$ 241,200,000