Allowance for Loan Losses (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				$ 8,200				$ 7,994	$ 8,200	$ 7,994
Charge-offs									(783)	(2,031)
Recoveries									99	377	236
Provisions for (reduction in) loan losses	1,421	1,284	1,030	949	596	646	322	296	4,684	1,860	751
Balance, at the end of the period	12,200				8,200				12,200	8,200	7,994
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans					105					105	665
Amount of allowance attributed to: General portfolio allocation	12,200				8,095				12,200	8,095
Loans individually evaluated for impairment	1,472				2,427				1,472	2,427
Specific reserves to total loans individually evaluated for impairment (as a percent)									0.00%	4.33%
Loans collectively evaluated for impairment	1,626,973				1,240,825				1,626,973	1,240,825
General reserves to total loans collectively evaluated for impairment (as a percent)									0.75%	0.65%
Total gross loans	1,628,445				1,243,252				1,628,445	1,243,252
Total allowance to gross loans (as a percent)									0.75%	0.66%
Commercial Business Loans, Owner-Occupied Commercial Real Estate Loans, and SBA Loans
Allowance for Loan Losses
Actual trailing period considered for determination of allowance for loan losses factor									84 months
Trailing period one considered for determination of allowance for loan losses factor									36 months
Trailing period two considered for determination of allowance for loan losses factor									24 months
Trailing period three considered for determination of allowance for loan losses factor									12 months
Annualized trailing period considered for determination of allowance for loan losses factor									6 months
Period considered for comparison of allowance for loan losses factor									10 years
Period considered for comparison of entity's allowance for loan losses factor									15 years
Trailing period considered for comparison of allowance for loan losses factor									12 months
Non-Owner Occupied Commercial Real Estate, Multi-Family, Land and Construction Loans
Allowance for Loan Losses
Actual trailing period considered for determination of allowance for loan losses factor									84 months
Trailing period one considered for determination of allowance for loan losses factor									36 months
Trailing period two considered for determination of allowance for loan losses factor									24 months
Trailing period three considered for determination of allowance for loan losses factor									12 months
Annualized trailing period considered for determination of allowance for loan losses factor									6 months
Period considered for comparison of allowance for loan losses factor									10 years
Period considered for comparison of entity's allowance for loan losses factor									15 years
Trailing period considered for comparison of allowance for loan losses factor									12 months
Single Family and Consumer Loans and Warehouse Repurchase Facilities
Allowance for Loan Losses
Actual trailing period considered for determination of allowance for loan losses factor									84 months
Trailing period one considered for determination of allowance for loan losses factor									36 months
Trailing period two considered for determination of allowance for loan losses factor									24 months
Trailing period three considered for determination of allowance for loan losses factor									12 months
Annualized trailing period considered for determination of allowance for loan losses factor									6 months
Period considered for comparison of allowance for loan losses factor									10 years
Period considered for comparison of entity's allowance for loan losses factor									15 years
Trailing period considered for comparison of allowance for loan losses factor									12 months
Business loans: Commercial and industrial
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				1,968				1,310	1,968	1,310
Charge-offs									(223)	(509)
Recoveries									42	138
Provisions for (reduction in) loan losses									2,413	1,029
Balance, at the end of the period	4,200				1,968				4,200	1,968
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans											270
Amount of allowance attributed to: General portfolio allocation	4,200				1,968				4,200	1,968
Specific reserves to total loans individually evaluated for impairment (as a percent)									0.00%	0.00%
Loans collectively evaluated for impairment	428,207				187,035				428,207	187,035
General reserves to total loans collectively evaluated for impairment (as a percent)									0.98%	1.05%
Total gross loans	428,207				187,035				428,207	187,035
Total allowance to gross loans (as a percent)									0.98%	1.05%
Business loans: Commercial owner occupied
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				1,818				1,512	1,818	1,512
Charge-offs										(232)
Provisions for (reduction in) loan losses									(61)	538
Balance, at the end of the period	1,757				1,818				1,757	1,818
Other disclosures
Amount of allowance attributed to: General portfolio allocation	1,757				1,818				1,757	1,818
Loans individually evaluated for impairment	388				747				388	747
Specific reserves to total loans individually evaluated for impairment (as a percent)									0.00%	0.00%
Loans collectively evaluated for impairment	210,607				220,342				210,607	220,342
General reserves to total loans collectively evaluated for impairment (as a percent)									0.83%	0.83%
Total gross loans	210,995				221,089				210,995	221,089
Total allowance to gross loans (as a percent)									0.83%	0.82%
Business loans: SBA
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				151				79	151	79
Charge-offs										(143)
Recoveries									4	50
Provisions for (reduction in) loan losses									413	165
Balance, at the end of the period	568				151				568	151
Other disclosures
Amount of allowance attributed to: General portfolio allocation	568				151				568	151
Loans individually evaluated for impairment					14					14
Specific reserves to total loans individually evaluated for impairment (as a percent)									0.00%	0.00%
Loans collectively evaluated for impairment	28,404				10,645				28,404	10,645
General reserves to total loans collectively evaluated for impairment (as a percent)									2.00%	1.42%
Total gross loans	28,404				10,659				28,404	10,659
Total allowance to gross loans (as a percent)									2.00%	1.42%
Business loans: Warehouse facilities
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				392				1,544	392	1,544
Provisions for (reduction in) loan losses									154	(1,152)
Balance, at the end of the period	546				392				546	392
Other disclosures
Amount of allowance attributed to: General portfolio allocation	546				392				546	392
Specific reserves to total loans individually evaluated for impairment (as a percent)									0.00%	0.00%
Loans collectively evaluated for impairment	113,798				87,517				113,798	87,517
General reserves to total loans collectively evaluated for impairment (as a percent)									0.48%	0.45%
Total gross loans	113,798				87,517				113,798	87,517
Total allowance to gross loans (as a percent)									0.48%	0.45%
Real estate loans: Commercial non-owner occupied
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				1,658				1,459	1,658	1,459
Charge-offs									(365)	(756)
Provisions for (reduction in) loan losses									714	955
Balance, at the end of the period	2,007				1,658				2,007	1,658
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans					1					1
Amount of allowance attributed to: General portfolio allocation	2,007				1,657				2,007	1,657
Loans individually evaluated for impairment	848				983				848	983
Specific reserves to total loans individually evaluated for impairment (as a percent)									0.00%	0.10%
Loans collectively evaluated for impairment	358,365				332,561				358,365	332,561
General reserves to total loans collectively evaluated for impairment (as a percent)									0.56%	0.50%
Total gross loans	359,213				333,544				359,213	333,544
Total allowance to gross loans (as a percent)									0.56%	0.50%
Real estate loans: Multi-family
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				817				1,145	817	1,145
Charge-offs										(101)
Provisions for (reduction in) loan losses									243	(227)
Balance, at the end of the period	1,060				817				1,060	817
Other disclosures
Amount of allowance attributed to: General portfolio allocation	1,060				817				1,060	817
Specific reserves to total loans individually evaluated for impairment (as a percent)									0.00%	0.00%
Loans collectively evaluated for impairment	262,965				233,689				262,965	233,689
General reserves to total loans collectively evaluated for impairment (as a percent)									0.40%	0.35%
Total gross loans	262,965				233,689				262,965	233,689
Total allowance to gross loans (as a percent)									0.40%	0.35%
Real estate loans: One-to-four family
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				1,099				862	1,099	862
Charge-offs									(195)	(272)
Recoveries									34	47
Provisions for (reduction in) loan losses									(96)	462
Balance, at the end of the period	842				1,099				842	1,099
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans					104					104	395
Amount of allowance attributed to: General portfolio allocation	842				995				842	995
Loans individually evaluated for impairment	236				683				236	683
Specific reserves to total loans individually evaluated for impairment (as a percent)									0.00%	15.23%
Loans collectively evaluated for impairment	122,559				144,552				122,559	144,552
General reserves to total loans collectively evaluated for impairment (as a percent)									0.69%	0.69%
Total gross loans	122,795				145,235				122,795	145,235
Total allowance to gross loans (as a percent)									0.69%	0.76%
Real estate loans: Construction
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				136					136
Provisions for (reduction in) loan losses									952	136
Balance, at the end of the period	1,088				136				1,088	136
Other disclosures
Amount of allowance attributed to: General portfolio allocation	1,088				136				1,088	136
Specific reserves to total loans individually evaluated for impairment (as a percent)									0.00%	0.00%
Loans collectively evaluated for impairment	89,682				13,040				89,682	13,040
General reserves to total loans collectively evaluated for impairment (as a percent)									1.21%	1.04%
Total gross loans	89,682				13,040				89,682	13,040
Total allowance to gross loans (as a percent)									1.21%	1.04%
Real estate loans: Land
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				127				31	127	31
Provisions for (reduction in) loan losses									(19)	96
Balance, at the end of the period	108				127				108	127
Other disclosures
Amount of allowance attributed to: General portfolio allocation	108				127				108	127
Specific reserves to total loans individually evaluated for impairment (as a percent)									0.00%	0.00%
Loans collectively evaluated for impairment	9,088				7,605				9,088	7,605
General reserves to total loans collectively evaluated for impairment (as a percent)									1.19%	1.67%
Total gross loans	9,088				7,605				9,088	7,605
Total allowance to gross loans (as a percent)									1.49%	1.67%
Other loans
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				34				52	34	52
Charge-offs										(18)
Recoveries									19	142
Provisions for (reduction in) loan losses									(29)	(142)
Balance, at the end of the period	24				34				24	34
Other disclosures
Amount of allowance attributed to: General portfolio allocation	24				34				24	34
Specific reserves to total loans individually evaluated for impairment (as a percent)									0.00%	0.00%
Loans collectively evaluated for impairment	3,298				3,839				3,298	3,839
General reserves to total loans collectively evaluated for impairment (as a percent)									0.73%	0.89%
Total gross loans	$ 3,298				$ 3,839				$ 3,298	$ 3,839
Total allowance to gross loans (as a percent)									0.73%	0.89%