Loans Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for Loan Losses, Beginning Balance	$ 20,695	$ 19,640	$ 20,196	$ 18,586
Charge-offs	(402)	(325)	(1,232)	(960)
Recoveries	120	102	522	416
Provision	518	586	1,445	1,961
Allowance for Loan Losses, Ending Balance	20,931	20,003	20,931	20,003
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	5	177	5	177	$ 4
Allowance for loan losses - Loans Collectively Evaluated for Impairment	20,926	19,826	20,926	19,826	20,192
Ending Loan Balance - Individually Evaluated for Impairment	724	3,423	724	3,423	3,223
Ending Loan Balance - Collectively Evaluated for Impairment	2,334,867	2,122,677	2,334,867	2,122,677	2,192,992
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for Loan Losses, Beginning Balance	1,231	944	1,218	1,873
Charge-offs	(11)	0	(12)	(16)
Recoveries	0	0	98	1
Provision	42	99	(42)	(815)
Allowance for Loan Losses, Ending Balance	1,262	1,043	1,262	1,043
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	5	84	5	84	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	1,257	959	1,257	959	1,218
Ending Loan Balance - Individually Evaluated for Impairment	36	489	36	489	430
Ending Loan Balance - Collectively Evaluated for Impairment	142,099	126,623	142,099	126,623	136,460
Commercial Real Estate Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for Loan Losses, Beginning Balance	5,459	5,838	5,644	4,504
Charge-offs	0	0	(29)	0
Recoveries	0	0	0	12
Provision	162	81	6	1,403
Allowance for Loan Losses, Ending Balance	5,621	5,919	5,621	5,919
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	45	0	45	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	5,621	5,874	5,621	5,874	5,644
Ending Loan Balance - Individually Evaluated for Impairment	0	812	0	812	793
Ending Loan Balance - Collectively Evaluated for Impairment	498,083	469,310	498,083	469,310	483,769
Consumer Loans Financing
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for Loan Losses, Beginning Balance	9,654	8,337	8,882	7,604
Charge-offs	(351)	(300)	(1,137)	(895)
Recoveries	120	102	424	403
Provision	263	551	1,517	1,578
Allowance for Loan Losses, Ending Balance	9,686	8,690	9,686	8,690
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	0	0	0	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	9,686	8,690	9,686	8,690	8,882
Ending Loan Balance - Individually Evaluated for Impairment	113	109	113	109	101
Ending Loan Balance - Collectively Evaluated for Impairment	805,684	694,079	805,684	694,079	719,409
Residential
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for Loan Losses, Beginning Balance	4,351	4,521	4,452	4,605
Charge-offs	(40)	(25)	(54)	(49)
Recoveries	0	0	0	0
Provision	51	(145)	(36)	(205)
Allowance for Loan Losses, Ending Balance	4,362	4,351	4,362	4,351
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	48	0	48	4
Allowance for loan losses - Loans Collectively Evaluated for Impairment	4,362	4,303	4,362	4,303	4,448
Ending Loan Balance - Individually Evaluated for Impairment	575	2,013	575	2,013	1,899
Ending Loan Balance - Collectively Evaluated for Impairment	$ 889,001	$ 832,665	$ 889,001	$ 832,665	$ 853,354

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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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 writeoff of financing receivable, charged against allowance for credit loss.

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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 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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