Income Taxes (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Operating Loss Carryforwards
Excess tax benefit from stock option deductions	$ 9,200,000								$ 9,200,000
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest [Abstract]
Income (loss) from continuing operations before income taxes									(17,964,000)	32,531,000	(52,534,000)
Income tax (expense) benefit allocated to continuing operations									(4,700,000)	(2,300,000)	11,700,000
Income (loss) from continuing operations	(42,000,000)	6,800,000	12,900,000	(300,000)	17,700,000	11,800,000	(5,200,000)	5,900,000	(22,639,000)	30,196,000	(40,841,000)
Income (loss) from discontinued operations before income taxes									(9,400,000)	(32,900,000)	27,100,000
Income tax (expense) benefit allocated to discontinued operations									200,000	200,000	(9,700,000)
Income (loss) from discontinued operations	(400,000)	(7,100,000)	(1,000,000)	(700,000)	7,300,000	(12,600,000)	(23,900,000)	(3,600,000)	(9,166,000)	(32,735,000)	17,422,000
Net loss	(42,400,000)	(300,000)	12,000,000	(1,000,000)	25,000,000	(800,000)	(29,100,000)	2,400,000	(31,805,000)	(2,539,000)	(23,419,000)
Income tax (expense) benefit allocated to other comprehensive income									0	200,000	0
Alternative minimum tax	3,100,000								3,100,000
General business credit	15,300,000								15,300,000
Foreign tax credit	10,400,000								10,400,000
Operating loss carryforwards									20 years
Domestic Tax Authority
Operating Loss Carryforwards
Operating loss carryforwards	271,000,000								271,000,000
State and Local Jurisdiction
Operating Loss Carryforwards
Operating loss carryforwards	$ 214,000,000								$ 214,000,000