Income Taxes (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Deferred tax assets	$ 124,268,000	$ 152,038,000
Income tax credits and adjustments	6,800,000	8,900,000
Deferred tax assets, tax credit carry forwards, alternative minimum tax	0	4,300,000
State tax credits benefit period	five
State tax credits, carry forward period	eight
Unrecognized tax benefits	550,000	589,000	2,263,000
Unrecognized tax benefits, decreases resulting from settlements with taxing authorities	(39,000)
Unrecognized tax benefits, Interest on income taxes expense	4,000	194,000
Effective income tax rate on unrecognized tax benefits that would impact effective tax rate	0.30%
Accrued interest related to unrecognized tax benefits	167,000	171,000
Carry forward period of federal low income housing credits	20
Net operating loss carryforwards	1,291,000	8,897,000
California [Member]
Unrecognized tax benefits, decreases resulting from settlements with taxing authorities	$ 39,000	$ 1,700,000
Net operating loss carryforward maximum period	20