Allowance for Loan Losses (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011
Valuation Allowance for Impairment of Recognized Servicing Assets [Line Items]
Allowance for loan losses	$ (417,000)		$ (417,000)			$ (2,499,000)
Commercial [Member]
Valuation Allowance for Impairment of Recognized Servicing Assets [Line Items]
Unpaid principal balance of impaired securitized loans	0		0			4,724,000
Basis adjustments related to impaired securitized loans	0		0			8,000
Amortized cost basis of impaired securitized loans	0		0			4,732,000
Allowance for loan losses	(150,000)		(150,000)			(2,268,000)
Impaired Financing Receivable, with Related Allowance, Recorded Investment	(150,000)		(150,000)			2,464,000
Interest income recognized on impaired securitized loans	0	27	50	83
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance at beginning of period			2,268,000	4,200,000	1,355,000		3,069,000
Provision for loan losses	(36,000)	300,000	24,000	750,000
Credit losses, net of recoveries	(1,169,000)	(1,196,000)	(2,142,000)	(2,777,000)
Allowance at end of period	150,000	2,173,000	150,000	2,173,000	1,355,000		3,069,000
Single-family [Member]
Valuation Allowance for Impairment of Recognized Servicing Assets [Line Items]
Unpaid principal balance of impaired securitized loans	3,382,000		3,382,000			3,000,000
Basis adjustments related to impaired securitized loans	51,000		51,000			48,000
Amortized cost basis of impaired securitized loans	3,433,000		3,433,000			3,048,000
Allowance for loan losses	(267,000)		(267,000)			(231,000)
Impaired Financing Receivable, with Related Allowance, Recorded Investment	3,166,000		3,166,000			2,817,000
Interest income recognized on impaired securitized loans	47	49	141	146
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance at beginning of period			231,000	270,000	231,000		208,000
Provision for loan losses	146,000	0	146,000	0
Credit losses, net of recoveries	(110,000)	0	(110,000)	(62,000)
Allowance at end of period	$ 267,000	$ 208,000	$ 267,000	$ 208,000	$ 231,000		$ 208,000