Loans - Balance in the Allowance for Loan Losses and the Recorded Investment in Loans by Portfolio Segment, Based on the Impairment Method (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Balance in the Allowance for Loan Losses and the Recorded Investment in Loans by Portfolio Segment, Based on the Impairment Method
Allowance for loan losses, Individually evaluated for impairment	$ 1,441	$ 329
Allowance for loan losses, Collectively evaluated for impairment	17,694	18,760
Total allowance balance	19,135	19,089	$ 19,458	$ 18,926
Loans, Individually evaluated for impairment	5,288	2,945
Loans, Collectively evaluated for impairment	1,508,646	1,500,177
Loans, Acquired with deteriorated credit quality	245	245
Loans and Leases Receivable, Gross	1,514,179	1,503,367
Commercial
Balance in the Allowance for Loan Losses and the Recorded Investment in Loans by Portfolio Segment, Based on the Impairment Method
Allowance for loan losses, Individually evaluated for impairment	1,441	329
Allowance for loan losses, Collectively evaluated for impairment	9,811	10,327
Total allowance balance	11,252	10,656	11,279	10,748
Loans, Individually evaluated for impairment	3,929	2,057
Loans, Collectively evaluated for impairment	605,179	602,029
Loans, Acquired with deteriorated credit quality	245	245
Loans and Leases Receivable, Gross	609,353	604,331
Real estate
Balance in the Allowance for Loan Losses and the Recorded Investment in Loans by Portfolio Segment, Based on the Impairment Method
Allowance for loan losses, Collectively evaluated for impairment	7,743	8,327
Total allowance balance	7,743	8,327	8,068	8,076
Loans, Individually evaluated for impairment	1,357	885
Loans, Collectively evaluated for impairment	889,662	877,691
Loans and Leases Receivable, Gross	891,019	878,576
Consumer
Balance in the Allowance for Loan Losses and the Recorded Investment in Loans by Portfolio Segment, Based on the Impairment Method
Allowance for loan losses, Collectively evaluated for impairment	140	106
Total allowance balance	140	106	$ 111	$ 102
Loans, Individually evaluated for impairment	2	3
Loans, Collectively evaluated for impairment	13,805	20,457
Loans and Leases Receivable, Gross	$ 13,807	$ 20,460

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 15
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-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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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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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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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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