Allowance for Loan Losses Risk Ratings by Segment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	$ 670,955	$ 628,066
Commercial | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	372,810	353,243
Commercial | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	38,084	27,304
Commercial | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	218,773	196,391
Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	41,288	51,128
1 Strong
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	4,290	3,444
1 Strong | Commercial | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	0	0
1 Strong | Commercial | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	0	0
1 Strong | Commercial | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	4,258	3,444
1 Strong | Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	32	0
2 Above average
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	57,664	63,885
2 Above average | Commercial | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	12,393	10,484
2 Above average | Commercial | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	794	37
2 Above average | Commercial | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	6,187	4,564
2 Above average | Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	38,290	48,800
3 Satisfactory
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	118,920	129,105
3 Satisfactory | Commercial | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	74,709	80,266
3 Satisfactory | Commercial | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	2,305	2,231
3 Satisfactory | Commercial | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	41,527	46,090
3 Satisfactory | Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	379	518
4 Average
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	334,503	275,268
4 Average | Commercial | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	205,510	172,597
4 Average | Commercial | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	19,017	18,780
4 Average | Commercial | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	107,389	82,081
4 Average | Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	2,587	1,810
5 Watch
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	126,222	117,841
5 Watch | Commercial | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	63,582	66,325
5 Watch | Commercial | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	15,488	5,970
5 Watch | Commercial | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	47,152	45,546
5 Watch | Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	0	0
6 OAEM
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	3,148	8,695
6 OAEM | Commercial | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	1,160	6,890
6 OAEM | Commercial | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	0	0
6 OAEM | Commercial | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	1,988	1,805
6 OAEM | Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	0	0
8 Doubtful
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	26,208	29,705
8 Doubtful | Commercial | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	15,456	16,558
8 Doubtful | Commercial | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	480	286
8 Doubtful | Commercial | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	10,272	12,861
8 Doubtful | Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	0	0
8 Doubtful
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	0	123
8 Doubtful | Commercial | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	0	123
8 Doubtful | Commercial | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	0	0
8 Doubtful | Commercial | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	0	0
8 Doubtful | Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Risk rated loans receivable	$ 0	$ 0