Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	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
Current income tax provision:
Federal									$ 6,403	$ 3,781	$ 1,697
State									2,026	1,386	602
Total current income tax provision									8,429	5,167	2,299
Deferred income tax provision (benefit):
Federal									1,262	899	(121)
State									298	345	(95)
Total deferred income tax provision (benefit)									1,560	1,244	(216)
Total income tax provision	2,421	2,126	3,795	1,647	1,519	1,485	303	3,104	9,989	6,411	2,083
Reconciliation from statutory federal income taxes to the company's effective income taxes
Statutory federal income tax provision									8,760	5,774	2,149
California franchise tax net of federal income tax effect									1,842	1,214	335
Other, including tax exempt income									(613)	(577)	(401)
Total income tax provision	2,421	2,126	3,795	1,647	1,519	1,485	303	3,104	9,989	6,411	2,083
Deferred tax assets:
Accrued expenses	442				652				442	652
Depreciation on premises and equipment					98					98
Net operating loss	3,673				4,283				3,673	4,283
Allowance for loan losses, net of bad debt charge-offs	3,390				3,507				3,390	3,507
State taxes	765				471				765	471
Capital loss on mutual funds	281				814				281	814
Other-than-temporary impairment	2,180				2,068				2,180	2,068
Restricted stock and options expense	6				6				6	6
Other	147				73				147	73
Total deferred tax assets	10,884				11,972				10,884	11,972
Deferred tax liabilities:
Federal Home Loan Bank stock dividends	(560)				(758)				(560)	(758)
Deferred FDIC gain	(2,367)				(1,641)				(2,367)	(1,641)
Depreciation	(111)								(111)
Unrealized gain on available for sale securities	(772)				(221)				(772)	(221)
Other	(187)				(354)				(187)	(354)
Total deferred tax liabilities	(3,997)				(2,974)				(3,997)	(2,974)
Net deferred tax asset	$ 6,887				$ 8,998				$ 6,887	$ 8,998