Allowance for Loan and Lease Losses - Changes in Allowance for Loan and Lease Losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 10,420	$ 9,689	$ 9,689
Charge-offs	(526)	(474)	(1,300)
Recoveries	367	514	789
(Credit) provision	297	212	1,242
Ending balance	10,558	9,941	10,420
Ending balance: related to loans individually evaluated for impairment	251	210	368
Ending balance: related to loans collectively evaluated for impairment	10,307	9,731	10,052
LHFI [Abstract]
Ending balance	618,784	531,147	602,009
Ending balance: individually evaluated for impairment	6,939	6,466	6,955
Ending balance: collectively evaluated for impairment	611,845	524,681	595,054
Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	3,295	3,622	3,622
Charge-offs	(20)	(77)	(84)
Recoveries	0	176	201
(Credit) provision	91	(151)	(444)
Ending balance	3,366	3,570	3,295
Ending balance: related to loans individually evaluated for impairment	59	0	3
Ending balance: related to loans collectively evaluated for impairment	3,307	3,570	3,292
LHFI [Abstract]
Ending balance	266,421	237,343	261,561
Ending balance: individually evaluated for impairment	1,374	1,368	904
Ending balance: collectively evaluated for impairment	265,047	235,975	260,657
Construction and land development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,294	1,674	1,674
Charge-offs	0	0	0
Recoveries	351	194	306
(Credit) provision	(240)	52	314
Ending balance	2,405	1,920	2,294
Ending balance: related to loans individually evaluated for impairment	0	0	0
Ending balance: related to loans collectively evaluated for impairment	2,405	1,920	2,294
LHFI [Abstract]
Ending balance	88,561	61,095	83,369
Ending balance: individually evaluated for impairment	128	145	144
Ending balance: collectively evaluated for impairment	88,433	60,950	83,225
Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,346	1,513	1,513
Charge-offs	0	(108)	(107)
Recoveries	0	123	174
(Credit) provision	32	(109)	(234)
Ending balance	1,378	1,419	1,346
Ending balance: related to loans individually evaluated for impairment	0	0	0
Ending balance: related to loans collectively evaluated for impairment	1,378	1,419	1,346
LHFI [Abstract]
Ending balance	115,131	92,189	108,146
Ending balance: individually evaluated for impairment	1,875	2,317	2,105
Ending balance: collectively evaluated for impairment	113,256	89,872	106,041
Multi-family
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	263	171	171
Charge-offs	0	0	0
Recoveries	0	0	0
(Credit) provision	50	3	92
Ending balance	313	174	263
Ending balance: related to loans individually evaluated for impairment	0	0	0
Ending balance: related to loans collectively evaluated for impairment	313	174	263
LHFI [Abstract]
Ending balance	27,069	16,576	23,389
Ending balance: individually evaluated for impairment	0	0	0
Ending balance: collectively evaluated for impairment	27,069	16,576	23,389
Residential real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	656	586	586
Charge-offs	0	0	(40)
Recoveries	7	11	35
(Credit) provision	(12)	(11)	75
Ending balance	651	586	656
Ending balance: related to loans individually evaluated for impairment	17	25	17
Ending balance: related to loans collectively evaluated for impairment	634	561	639
LHFI [Abstract]
Ending balance	56,790	49,370	56,899
Ending balance: individually evaluated for impairment	636	843	653
Ending balance: collectively evaluated for impairment	56,154	48,527	56,246
Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,295	1,749	1,749
Charge-offs	(497)	(283)	(930)
Recoveries	9	8	57
(Credit) provision	432	519	1,419
Ending balance	2,239	1,993	2,295
Ending balance: related to loans individually evaluated for impairment	175	185	340
Ending balance: related to loans collectively evaluated for impairment	2,064	1,808	1,955
LHFI [Abstract]
Ending balance	58,733	67,267	61,838
Ending balance: individually evaluated for impairment	1,192	755	1,242
Ending balance: collectively evaluated for impairment	57,541	66,512	60,596
Tax certificates
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	242	347	347
Charge-offs	(9)	(6)	(139)
Recoveries	0	2	14
(Credit) provision	(54)	(91)	20
Ending balance	179	252	242
Ending balance: related to loans individually evaluated for impairment	0	0	8
Ending balance: related to loans collectively evaluated for impairment	179	252	234
LHFI [Abstract]
Ending balance	3,114	4,820	3,705
Ending balance: individually evaluated for impairment	1,734	1,038	1,907
Ending balance: collectively evaluated for impairment	1,380	3,782	1,798
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	29	27	27
Charge-offs	0	0	0
Recoveries	0	0	2
(Credit) provision	(2)	0	0
Ending balance	27	27	29
Ending balance: related to loans individually evaluated for impairment	0	0	0
Ending balance: related to loans collectively evaluated for impairment	27	27	29
LHFI [Abstract]
Ending balance	2,965	2,487	3,102
Ending balance: individually evaluated for impairment	0	0	0
Ending balance: collectively evaluated for impairment	2,965	2,487	3,102
Unallocated [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	0	0	0
Charge-offs	0	0	0
Recoveries	0	0	0
(Credit) provision	0	0	0
Ending balance	0	0	0
Ending balance: related to loans individually evaluated for impairment	0	0	0
Ending balance: related to loans collectively evaluated for impairment	0	0	0
LHFI [Abstract]
Ending balance	0	0	0
Ending balance: individually evaluated for impairment	0	0	0
Ending balance: collectively evaluated for impairment	$ 0	$ 0	$ 0

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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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No definition available.

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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
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

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-Publisher FASB
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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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