Allowance for Loan Losses - Allowance For Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of period	$ 18,183	$ 16,947	$ 18,153	$ 16,723
Charge-Offs	(135)	0	(869)	(188)
Recoveries	137	95	198	181
Provision (benefit)	200	376	903	702
Balance, end of period	18,385	17,418	18,385	17,418
Balance, end of period: Individually evaluated for impairment	227	265	227	265
Balance, end of period: collectively evaluated for impairment	18,158	17,153	18,158	17,153
Commercial
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of period	5,749	6,091	5,906	5,643
Charge-Offs	(135)	0	(868)	(107)
Recoveries	135	91	193	158
Provision (benefit)	118	(495)	636	(7)
Balance, end of period	5,867	5,687	5,867	5,687
Balance, end of period: Individually evaluated for impairment	0	265	0	265
Balance, end of period: collectively evaluated for impairment	5,867	5,422	5,867	5,422
Real estate construction one-to-four family
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of period	760	757	854	644
Charge-Offs	0	0	0	0
Recoveries	0	0	0	0
Provision (benefit)	132	(68)	38	45
Balance, end of period	892	689	892	689
Balance, end of period: Individually evaluated for impairment	204	0	204	0
Balance, end of period: collectively evaluated for impairment	688	689	688	689
Real estate construction other
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of period	1,621	1,663	1,439	1,653
Charge-Offs	0	0	0	0
Recoveries	0	0	0	0
Provision (benefit)	(524)	200	(342)	210
Balance, end of period	1,097	1,863	1,097	1,863
Balance, end of period: Individually evaluated for impairment	0	0	0	0
Balance, end of period: collectively evaluated for impairment	1,097	1,863	1,097	1,863
Real estate term owner occupied
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of period	1,739	1,570	1,657	1,580
Charge-Offs	0	0	0	0
Recoveries	0	0	0	0
Provision (benefit)	546	(100)	628	(110)
Balance, end of period	2,285	1,470	2,285	1,470
Balance, end of period: Individually evaluated for impairment	0	0	0	0
Balance, end of period: collectively evaluated for impairment	2,285	1,470	2,285	1,470
Real estate term non-owner occupied
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of period	5,498	4,794	5,515	4,704
Charge-Offs	0	0	0	0
Recoveries	0	0	0	0
Provision (benefit)	(200)	94	(217)	184
Balance, end of period	5,298	4,888	5,298	4,888
Balance, end of period: Individually evaluated for impairment	0	0	0	0
Balance, end of period: collectively evaluated for impairment	5,298	4,888	5,298	4,888
Real estate term other
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of period	638	756	628	656
Charge-Offs	0	0	0	(81)
Recoveries	0	0	0	17
Provision (benefit)	32	(85)	42	79
Balance, end of period	670	671	670	671
Balance, end of period: Individually evaluated for impairment	0	0	0	0
Balance, end of period: collectively evaluated for impairment	670	671	670	671
Consumer secured by 1st deeds of trust
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of period	264	274	264	285
Charge-Offs	0	0	0	0
Recoveries	0	0	0	0
Provision (benefit)	82	(9)	82	(20)
Balance, end of period	346	265	346	265
Balance, end of period: Individually evaluated for impairment	23	0	23	0
Balance, end of period: collectively evaluated for impairment	323	265	323	265
Consumer other
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of period	396	402	397	410
Charge-Offs	0	0	(1)	0
Recoveries	2	4	5	6
Provision (benefit)	22	9	19	(1)
Balance, end of period	420	415	420	415
Balance, end of period: Individually evaluated for impairment	0	0	0	0
Balance, end of period: collectively evaluated for impairment	420	415	420	415
Unallocated
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of period	1,518	640	1,493	1,148
Charge-Offs	0	0	0	0
Recoveries	0	0	0	0
Provision (benefit)	(8)	830	17	322
Balance, end of period	1,510	1,470	1,510	1,470
Balance, end of period: Individually evaluated for impairment	0	0	0	0
Balance, end of period: collectively evaluated for impairment	$ 1,510	$ 1,470	$ 1,510	$ 1,470