Income Taxes (Narrative) (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
Income Tax Contingency [Line Items]
State deferred taxes for capital losses	$ 2,500,000								$ 2,500,000
Income tax receivables	39,300,000								39,300,000
Federal net operating loss carry forward	2,000,000								2,000,000
Unrecognized tax benefits	508,000				519,000				508,000	519,000	2,593,000
Income taxes paid									53,148,000	13,369,000	25,247,000
Income tax benefit	14,459,000	14,162,000	10,906,000	11,734,000	6,789,000	7,023,000	(5,373,000)	(23,068,000)	51,261,000	(14,629,000)	(61,912,000)
Expiration of statute of limitations										(508,000)
Federal impact of state payments					843,000					843,000
Accrued interest and penalties					100,000					100,000
Net Operating Loss For 2009 To The 2007 Tax Year [Member]
Income Tax Contingency [Line Items]
Income tax receivables	11,200,000								11,200,000
Low Income Housing Tax Credits For 2009 To The 2008 Tax Year [Member]
Income Tax Contingency [Line Items]
Income tax receivables	9,100,000								9,100,000
Other Assets [Member]
Income Tax Contingency [Line Items]
Income tax receivables					23,500,000					23,500,000
State Taxes [Member]
Income Tax Contingency [Line Items]
Unrecognized tax benefits	100,000								100,000
Income taxes paid										800,000
California [Member]
Income Tax Contingency [Line Items]
Income taxes paid										1,500,000
Income tax benefit										500,000
Interest on income tax paid										900,000
Maximum [Member]
Income Tax Contingency [Line Items]
Accrued interest and penalties	$ 100,000								$ 100,000