Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Jun. 30, 2013	Jun. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Taxes
Total tax provision (benefit)	$ (164)	$ (1,533)	$ 621	$ (2,139)	$ (672)	$ (3,633)	$ (654)	$ 58,389	$ (912)	$ (4,287)	$ (1,076)	$ (4,959)	$ 1,916	$ 7,098	$ (58,389)
State													1,141	1,183	1,047
Income tax benefit attributable to the partial reduction of deferred income tax valuation allowance								59,763
Valuation allowances related to capital losses which were used to offset a capital gain					1,156							1,156
Income Taxes
Tax credit carry forward, which begins to expire in 2022 if unused													15,235
Tax benefit recognized from discontinued operations													(3,539)	5,441	(2,803)
Federal
Income Taxes
Net operating loss carry forward, which begins to expire in 2025 if unused													78,036
Net operating losses attributable to stock option exercises													$ 278