Loans - Past-due Status of Loans by Class (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Schedule of Financing Receivables [Line Items]
All Past Due	$ 11,280	$ 13,375	$ 15,867
Current	1,253,359	1,224,908	1,172,135
Total	1,264,639	1,238,283	1,188,002
90 Days or More & Accruing	4	351	137
30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	6,048	5,958	11,940
60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	2,215	3,977	860
90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	3,017	3,440	3,067
Commercial \| Real estate
Schedule of Financing Receivables [Line Items]
All Past Due	1,728	2,051	1,182
Current	356,032	351,192	338,124
Total	357,760	353,243	339,306
90 Days or More & Accruing	0	0	0
Commercial \| Real estate \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	282	1,274	963
Commercial \| Real estate \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	825	0	17
Commercial \| Real estate \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	621	777	202
Commercial \| Construction
Schedule of Financing Receivables [Line Items]
All Past Due	333	10	347
Current	33,898	27,294	43,466
Total	34,231	27,304	43,813
90 Days or More & Accruing	0	0	0
Commercial \| Construction \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	47	0	347
Commercial \| Construction \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	10	0
Commercial \| Construction \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	286	0	0
Commercial \| Other
Schedule of Financing Receivables [Line Items]
All Past Due	1,030	580	7,233
Current	204,432	195,811	170,550
Total	205,462	196,391	177,783
90 Days or More & Accruing	0	0	0
Commercial \| Other \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	664	455	6,887
Commercial \| Other \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	63	5	52
Commercial \| Other \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	303	120	294
Municipal
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Current	54,246	51,128	35,463
Total	54,246	51,128	35,463
90 Days or More & Accruing	0	0	0
Municipal \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Municipal \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Municipal \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Residential \| Construction
Schedule of Financing Receivables [Line Items]
All Past Due	0	76	0
Current	18,450	17,667	15,847
Total	18,450	17,743	15,847
90 Days or More & Accruing	0	0	0
Residential \| Construction \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	76	0
Residential \| Construction \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Residential \| Construction \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Residential \| Term
Schedule of Financing Receivables [Line Items]
All Past Due	5,246	6,638	5,400
Current	468,995	462,507	434,584
Total	474,241	469,145	439,984
90 Days or More & Accruing	0	339	0
Residential \| Term \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	2,659	1,097	3,175
Residential \| Term \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	1,153	3,518	345
Residential \| Term \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	1,434	2,023	1,880
Home equity line of credit
Schedule of Financing Receivables [Line Items]
All Past Due	2,365	3,731	1,551
Current	93,327	94,738	108,747
Total	95,692	98,469	110,298
90 Days or More & Accruing	0	0	126
Home equity line of credit \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	1,985	2,819	449
Home equity line of credit \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	11	419	438
Home equity line of credit \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	369	493	664
Consumer
Schedule of Financing Receivables [Line Items]
All Past Due	578	289	154
Current	23,979	24,571	25,354
Total	24,557	24,860	25,508
90 Days or More & Accruing	4	12	11
Consumer \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	411	237	119
Consumer \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	163	25	8
Consumer \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	$ 4	$ 27	$ 27

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Recorded investment in financing receivables that are 90 days or more past due and still accruing.

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Financing receivables that are current.

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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.

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