Investments (Details) (USD $)	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Schedule of available-for-sale securities [Line Items]
Amortized cost	$ 21,608,000		$ 3,992,000
Gross unrealized gains	33,000		6,000
Gross unrealized losses 1 year or less	(178,000)		0
Gross unrealized losses greater than 1 year	(572,000)		(1,006,000)
Estimated fair value	20,891,000		2,992,000
Available-for-sale securities, contractual maturities [Abstract]
Due after ten years, amortized cost	21,608,000
Due after ten years, fair value	20,891,000
Securities pledged as collateral	57,000
Letters of credit to secure deposits	30,000,000
Gross realized gain (loss), disclosures [Abstract]
Proceeds	0	1,118,000
Gross gains	0	3,000
Gross losses	0	(36,000)
Continuous unrealized loss position, fair value [Abstract]
Less than twelve months	13,645,000		0
Twelve months or longer	2,828,000		2,933,000
Total	16,473,000		2,933,000
Continuous unrealized loss position, unrealized loss [Abstract]
Less than 12 months	(178,000)		0
Twelve months or longer	2,828,000		(1,006,000)
Total	(750,000)		(1,006,000)
Other than temporary impairment, credit losses recognized in earnings [Roll Forward]
Estimated credit losses, beginning balance	256,000	160,000
Additions for credit losses not previously recognized	156,000	96,000
Reduction for increases in cash flows	0	0
Reduction for realized losses	0	0
Estimated losses, ending balance	412,000	256,000
Number of securities reflecting OTTI	4
Agency mortgage-backed securities [Member]
Schedule of available-for-sale securities [Line Items]
Amortized cost	18,208,000		53,000
Gross unrealized gains	33,000		6,000
Gross unrealized losses 1 year or less	(178,000)		0
Gross unrealized losses greater than 1 year	0		0
Estimated fair value	18,063,000		59,000
Continuous unrealized loss position, fair value [Abstract]
Less than twelve months	13,645,000
Twelve months or longer	0
Total	13,645,000
Continuous unrealized loss position, unrealized loss [Abstract]
Less than 12 months	(178,000)
Twelve months or longer	0
Total	(178,000)
Other than temporary impairment, credit losses recognized in earnings [Roll Forward]
Number of portfolio securities	14
Number of securities in unrealized loss position	9
Non-agency mortgage-backed securities [Member]
Schedule of available-for-sale securities [Line Items]
Amortized cost	3,400,000		3,939,000
Gross unrealized gains	0		0
Gross unrealized losses 1 year or less	0		0
Gross unrealized losses greater than 1 year	(572,000)		(1,006,000)
Estimated fair value	2,828,000		2,933,000
Continuous unrealized loss position, fair value [Abstract]
Less than twelve months	0		0
Twelve months or longer	2,828,000		2,933,000
Total	2,828,000		2,933,000
Continuous unrealized loss position, unrealized loss [Abstract]
Less than 12 months	0		0
Twelve months or longer	(572,000)		(1,006,000)
Total	$ (572,000)		$ (1,006,000)
Other than temporary impairment, credit losses recognized in earnings [Roll Forward]
Number of portfolio securities	5
Number of securities in unrealized loss position	5