Allowance for Loan and Lease Losses - Changes in Allowance for Loan and Lease Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 10,036	$ 11,569	$ 11,708	$ 13,671	$ 13,671
Charge-offs	(177)	(271)	(1,639)	(1,699)	(2,121)
Recoveries	163	235	1,119	275	1,025
(Credit) provision	(216)	(51)	(1,382)	(765)	(867)
Ending balance	9,806	11,482	9,806	11,482	11,708
Ending balance: related to loans individually evaluated for impairment	322	493	322	493	1,041
Ending balance: related to loans collectively evaluated for impairment	9,484	10,989	9,484	10,989	10,667
LHFI [Abstract]
Ending balance	471,216	397,176	471,216	397,176	415,132
Ending balance: individually evaluated for impairment	10,118	16,141	10,118	16,141	16,078
Ending balance: collectively evaluated for impairment	461,098	381,035	461,098	381,035	399,054
Commercial real estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	4,208	4,971	4,452	5,498	5,498
Charge-offs			(231)	(349)	(354)
Recoveries			351
(Credit) provision	(344)	(266)	(708)	(444)	(692)
Ending balance	3,864	4,705	3,864	4,705	4,452
Ending balance: related to loans individually evaluated for impairment		205		205	200
Ending balance: related to loans collectively evaluated for impairment	3,864	4,500	3,864	4,500	4,252
LHFI [Abstract]
Ending balance	210,883	164,522	210,883	164,522	175,038
Ending balance: individually evaluated for impairment	4,040	6,877	4,040	6,877	6,795
Ending balance: collectively evaluated for impairment	206,843	157,645	206,843	157,645	168,243
Construction and land development [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,358	2,033	2,292	2,316	2,316
Charge-offs	(39)		(119)		(172)
Recoveries	150	205	402	205	940
(Credit) provision	133	3	(973)	(280)	(792)
Ending balance	1,602	2,241	1,602	2,241	2,292
Ending balance: related to loans individually evaluated for impairment	145	172	145	172
Ending balance: related to loans collectively evaluated for impairment	1,457	2,069	1,457	2,069	2,292
LHFI [Abstract]
Ending balance	38,864	41,676	38,864	41,676	45,662
Ending balance: individually evaluated for impairment	290	1,192	290	1,192	683
Ending balance: collectively evaluated for impairment	38,574	40,484	38,574	40,484	44,979
Commercial and industrial [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,705	1,525	1,780	3,006	3,006
Charge-offs			(541)	(452)	(452)
Recoveries	4	12	278	23	27
(Credit) provision	(301)	(106)	(109)	(1,146)	(801)
Ending balance	1,408	1,431	1,408	1,431	1,780
Ending balance: related to loans individually evaluated for impairment		5		5	301
Ending balance: related to loans collectively evaluated for impairment	1,408	1,426	1,408	1,426	1,479
LHFI [Abstract]
Ending balance	82,414	70,743	82,414	70,743	76,489
Ending balance: individually evaluated for impairment	3,024	5,897	3,024	5,897	5,846
Ending balance: collectively evaluated for impairment	79,390	64,846	79,390	64,846	70,643
Multi-family [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	300	416	285	402	402
(Credit) provision	(113)	(63)	(98)	(49)	(117)
Ending balance	187	353	187	353	285
Ending balance: related to loans collectively evaluated for impairment	187	353	187	353	285
LHFI [Abstract]
Ending balance	15,222	16,893	15,222	16,893	13,823
Ending balance: collectively evaluated for impairment	15,222	16,893	15,222	16,893	13,823
Residential real estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	584	690	616	473	473
Recoveries	5	5	16	11	15
(Credit) provision	67	25	24	236	128
Ending balance	656	720	656	720	616
Ending balance: related to loans individually evaluated for impairment	28	30	28	30	28
Ending balance: related to loans collectively evaluated for impairment	628	690	628	690	588
LHFI [Abstract]
Ending balance	54,025	44,261	54,025	44,261	42,992
Ending balance: individually evaluated for impairment	918	983	918	983	959
Ending balance: collectively evaluated for impairment	53,107	43,278	53,107	43,278	42,033
Leases [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,405	1,352	1,429	1,223	1,223
Charge-offs	(138)	(206)	(315)	(568)	(793)
Recoveries	4	13	20	35	42
(Credit) provision	316	325	453	794	957
Ending balance	1,587	1,484	1,587	1,484	1,429
Ending balance: related to loans individually evaluated for impairment	131	62	131	62	80
Ending balance: related to loans collectively evaluated for impairment	1,456	1,422	1,456	1,422	1,349
LHFI [Abstract]
Ending balance	61,954	48,588	61,954	48,588	51,583
Ending balance: individually evaluated for impairment	640	64	640	64	95
Ending balance: collectively evaluated for impairment	61,314	48,524	61,314	48,524	51,488
Tax certificates [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	317	408	667	555	555
Charge-offs		(65)	(433)	(330)	(350)
Recoveries			52	1	1
(Credit) provision	38	29	69	146	461
Ending balance	355	372	355	372	667
Ending balance: related to loans individually evaluated for impairment	18	19	18	19	432
Ending balance: related to loans collectively evaluated for impairment	337	353	337	353	235
LHFI [Abstract]
Ending balance	5,294	8,230	5,294	8,230	7,191
Ending balance: individually evaluated for impairment	1,206	1,128	1,206	1,128	1,700
Ending balance: collectively evaluated for impairment	4,088	7,102	4,088	7,102	5,491
Consumer [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	35	24	38	15	15
(Credit) provision	(6)	9	(9)	18	23
Ending balance	29	33	29	33	38
Ending balance: related to loans collectively evaluated for impairment	29	33	29	33	38
LHFI [Abstract]
Ending balance	2,560	2,263	2,560	2,263	2,354
Ending balance: collectively evaluated for impairment	2,560	2,263	2,560	2,263	2,354
Unallocated [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	124	150	149	183	183
(Credit) provision	(6)	(7)	(31)	(40)	(34)
Ending balance	118	143	118	143	149
Ending balance: related to loans collectively evaluated for impairment	$ 118	$ 143	$ 118	$ 143	$ 149

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of direct write-downs of financing receivables charged against the allowance.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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