Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				$ 12,200	$ 8,200
Charge-offs				(836)	(783)
Recoveries				56	87
Provisions for (reduction in) loan losses	$ 1,062	$ 1,833	$ 1,284	4,725	3,263
Balance, at the end of the period	16,145		10,767	16,145	10,767
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans	0		0	0	0	$ 0
Amount of allowance attributed to: General portfolio allocation	16,145		10,767	16,145	10,767
Loans individually evaluated for impairment	2,659		1,807	$ 2,659	$ 1,807
Specific reserves to total loans individually evaluated for impairment (as a percent)				0.00%	0.00%
Loans collectively evaluated for impairment	2,164,888		1,546,104	$ 2,164,888	$ 1,546,104
General reserves to total loans collectively evaluated for impairment (as a percent)				0.75%	0.70%
Total gross loans	2,167,547		1,547,911	$ 2,167,547	$ 1,547,911	1,628,445
Total allowance to gross loans (as a percent)				0.74%	0.70%
Commercial and industrial
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				$ 2,646	$ 1,968
Charge-offs				(72)	(223)
Recoveries				35	33
Provisions for (reduction in) loan losses				730	655
Balance, at the end of the period	3,339		2,433	3,339	2,433
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans	0		0	0	0	0
Amount of allowance attributed to: General portfolio allocation	3,339		2,433	3,339	2,433
Loans individually evaluated for impairment	0		0	$ 0	$ 0
Specific reserves to total loans individually evaluated for impairment (as a percent)				0.00%	0.00%
Loans collectively evaluated for impairment	288,982		218,871	$ 288,982	$ 218,871
General reserves to total loans collectively evaluated for impairment (as a percent)				1.16%	1.11%
Total gross loans	288,982		218,871	$ 288,982	$ 218,871	228,979
Total allowance to gross loans (as a percent)				1.16%	1.11%
Franchise
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				$ 1,554	$ 0
Charge-offs				(764)	0
Recoveries				0	0
Provisions for (reduction in) loan losses				1,434	1,024
Balance, at the end of the period	2,224		1,024	2,224	1,024
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans	0		0	0	0
Amount of allowance attributed to: General portfolio allocation	2,224		1,024	2,224	1,024
Loans individually evaluated for impairment	1,630		0	$ 1,630	$ 0
Specific reserves to total loans individually evaluated for impairment (as a percent)				0.00%	0.00%
Loans collectively evaluated for impairment	294,335		163,887	$ 294,335	$ 163,887
General reserves to total loans collectively evaluated for impairment (as a percent)				0.76%	0.62%
Total gross loans	295,965		163,887	$ 295,965	$ 163,887	199,228
Total allowance to gross loans (as a percent)				0.75%	0.62%
Commercial owner occupied
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				$ 1,757	$ 1,818
Charge-offs				0	0
Recoveries				0	0
Provisions for (reduction in) loan losses				147	(44)
Balance, at the end of the period	1,904		1,774	1,904	1,774
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans	0		0	0	0	0
Amount of allowance attributed to: General portfolio allocation	1,904		1,774	1,904	1,774
Loans individually evaluated for impairment	361		398	$ 361	$ 398
Specific reserves to total loans individually evaluated for impairment (as a percent)				0.00%	0.00%
Loans collectively evaluated for impairment	302,195		215,540	$ 302,195	$ 215,540
General reserves to total loans collectively evaluated for impairment (as a percent)				0.63%	0.82%
Total gross loans	302,556		215,938	$ 302,556	$ 215,938	210,995
Total allowance to gross loans (as a percent)				0.63%	0.82%
SBA
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				$ 568	$ 151
Charge-offs				0	0
Recoveries				4	4
Provisions for (reduction in) loan losses				891	290
Balance, at the end of the period	1,463		445	1,463	445
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans	0		0	0	0	0
Amount of allowance attributed to: General portfolio allocation	1,463		445	1,463	445
Loans individually evaluated for impairment	0		0	$ 0	$ 0
Specific reserves to total loans individually evaluated for impairment (as a percent)				0.00%	0.00%
Loans collectively evaluated for impairment	70,191		20,482	$ 70,191	$ 20,482
General reserves to total loans collectively evaluated for impairment (as a percent)				2.08%	2.17%
Total gross loans	70,191		20,482	$ 70,191	$ 20,482	28,404
Total allowance to gross loans (as a percent)				2.08%	2.17%
Warehouse facilities
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				$ 546	$ 392
Charge-offs				0	0
Recoveries				0	0
Provisions for (reduction in) loan losses				258	102
Balance, at the end of the period	804		494	804	494
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans	0		0	0	0
Amount of allowance attributed to: General portfolio allocation	804		494	804	494
Loans individually evaluated for impairment	0		0	$ 0	$ 0
Specific reserves to total loans individually evaluated for impairment (as a percent)				0.00%	0.00%
Loans collectively evaluated for impairment	144,274		108,093	$ 144,274	$ 108,093
General reserves to total loans collectively evaluated for impairment (as a percent)				0.56%	0.46%
Total gross loans	144,274		108,093	$ 144,274	$ 108,093	113,798
Total allowance to gross loans (as a percent)				0.56%	0.46%
Commercial non-owner occupied
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				$ 2,007	$ 1,658
Charge-offs				0	(365)
Recoveries				3	0
Provisions for (reduction in) loan losses				111	608
Balance, at the end of the period	2,121		1,901	2,121	1,901
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans	0		0	0	0	0
Amount of allowance attributed to: General portfolio allocation	2,121		1,901	2,121	1,901
Loans individually evaluated for impairment	443		883	$ 443	$ 883
Specific reserves to total loans individually evaluated for impairment (as a percent)				0.00%	0.00%
Loans collectively evaluated for impairment	406,047		355,101	$ 406,047	$ 355,101
General reserves to total loans collectively evaluated for impairment (as a percent)				0.52%	0.54%
Total gross loans	406,490		355,984	$ 406,490	$ 355,984	359,213
Total allowance to gross loans (as a percent)				0.52%	0.53%
Multi-family
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				$ 1,060	$ 817
Charge-offs				0	0
Recoveries				0	0
Provisions for (reduction in) loan losses				620	194
Balance, at the end of the period	1,680		1,011	1,680	1,011
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans	0		0	0	0
Amount of allowance attributed to: General portfolio allocation	1,680		1,011	1,680	1,011
Loans individually evaluated for impairment	0		0	$ 0	$ 0
Specific reserves to total loans individually evaluated for impairment (as a percent)				0.00%	0.00%
Loans collectively evaluated for impairment	421,240		262,588	$ 421,240	$ 262,588
General reserves to total loans collectively evaluated for impairment (as a percent)				0.40%	0.39%
Total gross loans	421,240		262,588	$ 421,240	$ 262,588	262,965
Total allowance to gross loans (as a percent)				0.40%	0.39%
One-to-four family
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				$ 842	$ 1,099
Charge-offs				0	(195)
Recoveries				13	32
Provisions for (reduction in) loan losses				(137)	(121)
Balance, at the end of the period	718		815	718	815
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans	0		0	0	0	0
Amount of allowance attributed to: General portfolio allocation	718		815	718	815
Loans individually evaluated for impairment	203		526	$ 203	$ 526
Specific reserves to total loans individually evaluated for impairment (as a percent)				0.00%	0.00%
Loans collectively evaluated for impairment	78,578		124,800	$ 78,578	$ 124,800
General reserves to total loans collectively evaluated for impairment (as a percent)				0.91%	0.65%
Total gross loans	78,781		125,326	$ 78,781	$ 125,326	122,795
Total allowance to gross loans (as a percent)				0.91%	0.65%
Construction
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				$ 1,088	$ 136
Charge-offs				0	0
Recoveries				0	0
Provisions for (reduction in) loan losses				613	639
Balance, at the end of the period	1,701		775	1,701	775
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans	0		0	0	0
Amount of allowance attributed to: General portfolio allocation	1,701		775	1,701	775
Loans individually evaluated for impairment	0		0	$ 0	$ 0
Specific reserves to total loans individually evaluated for impairment (as a percent)				0.00%	0.00%
Loans collectively evaluated for impairment	141,293		67,118	$ 141,293	$ 67,118
General reserves to total loans collectively evaluated for impairment (as a percent)				1.20%	1.15%
Total gross loans	141,293		67,118	$ 141,293	$ 67,118	89,682
Total allowance to gross loans (as a percent)				1.20%	1.15%
Land
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				$ 108	$ 127
Charge-offs				0	0
Recoveries				0	0
Provisions for (reduction in) loan losses				63	(55)
Balance, at the end of the period	171		72	171	72
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans	0		0	0	0
Amount of allowance attributed to: General portfolio allocation	171		72	171	72
Loans individually evaluated for impairment	22		0	$ 22	$ 0
Specific reserves to total loans individually evaluated for impairment (as a percent)				0.00%	0.00%
Loans collectively evaluated for impairment	12,736		6,103	$ 12,736	$ 6,103
General reserves to total loans collectively evaluated for impairment (as a percent)				1.34%	1.18%
Total gross loans	12,758		6,103	$ 12,758	$ 6,103	9,088
Total allowance to gross loans (as a percent)				1.34%	1.18%
Other loans
Allocation of allowance as well as the activity in allowance
Balance, at the beginning of the period				$ 24	$ 34
Charge-offs				0	0
Recoveries				1	18
Provisions for (reduction in) loan losses				(5)	(29)
Balance, at the end of the period	20		23	20	23
Other disclosures
Amount of allowance attributed to: Specifically evaluated impaired loans	0		0	0	0
Amount of allowance attributed to: General portfolio allocation	20		23	20	23
Loans individually evaluated for impairment	0		0	$ 0	$ 0
Specific reserves to total loans individually evaluated for impairment (as a percent)				0.00%	0.00%
Loans collectively evaluated for impairment	5,017		3,521	$ 5,017	$ 3,521
General reserves to total loans collectively evaluated for impairment (as a percent)				0.40%	0.65%
Total gross loans	$ 5,017		$ 3,521	$ 5,017	$ 3,521	$ 3,298
Total allowance to gross loans (as a percent)				0.40%	0.65%
Owner Occupied Commercial Real Estate Loans, Commercial and Industrial Loans and SBA Loans
Allowance for Loan Losses
Annualized trailing period two considered for determination of allowance for loan losses factor (in months)				72 months
Annualized trailing period three considered for determination of allowance for loan losses factor (in months)				36 months
Annualized trailing period four considered for determination of allowance for loan losses factor (in months)				24 months
Annualized trailing period five considered for determination of allowance for loan losses factor (in months)				12 months
Annualized trailing period six considered for determination of allowance for loan losses factor (in months)				6 months
Period considered for comparison of allowance for loan losses factor (in years)				10 years
Period considered for comparison of entity's allowance for loan losses factor (in years)				15 years
Trailing period considered for comparison of allowance for loan losses factor (in months)				12 months
Multi-Family and Non-Owner Occupied Commercial Real Estate Loans
Allowance for Loan Losses
Annualized trailing period one considered for determination of allowance for loan losses factor (in months)				84 months