Income Taxes (Details Textual) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012 M	Jun. 30, 2011	Dec. 31, 2011
Income Taxes (Textual) [Abstract]
Income tax expense (benefit)	$ 10,205,000	$ 2,941,000	$ 17,984,000	$ (16,000)
(Loss) income before income taxes	(14,851,000)	29,345,000	3,197,000	40,433,000
Tax on investment security settlement received		2,900,000
Payment of federal and state income taxes	700,000	400,000	800,000	500,000
Discrete benefit for reversal of portion of valuation allowance on domestic deferred tax assets				3,500,000
Interest and penalties for unrecognized tax benefits	100,000		200,000
Accrued interest and penalties for unrecognized tax benefits	1,700,000		1,700,000		1,600,000
Time period within which Notice of Deficiency is expected (in months)			12
2007, 2008 and 2009 Tax Returns [Member]
Other Tax Carryforward [Line Items]
Cumulative deductions taken for net securities losses			955,000,000
Cumulative benefit recognized on deductions for net security losses	$ 136,100,000		$ 136,100,000