Impaired Loan Information by Portfolio (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		$ 980	$ 1,079
Related Allowance		980	1,079
Recorded Investment		49,628	59,060
Unpaid Principal Balance		68,140	68,514
Average Recorded Investment	$ 63,522	59,682	63,522
Interest Income Recognized		1,537	1,554
Commercial and Industrial [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		126	7
Commercial Real Estate [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		48	37
Construction Loans [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		0
Small Business [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		8	1
Residential Real Estate [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		637	862
Home Equity [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		156	164
Consumer Portfolio Segment [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		5	8
With No Related Allowance Recorded [Member]
Impaired loans by loan portfolio
Recorded Investment		39,242	47,900
Unpaid Principal Balance		56,605	56,125
Average Recorded Investment		49,077	51,970
Interest Income Recognized		1,090	1,111
Related Allowance		0	0
With No Related Allowance Recorded [Member] \| Commercial and Industrial [Member]
Impaired loans by loan portfolio
Recorded Investment		23,786	28,459
Unpaid Principal Balance		34,970	35,913
Average Recorded Investment		27,056	31,117
Interest Income Recognized		136	142
Related Allowance		0	0
With No Related Allowance Recorded [Member] \| Commercial Real Estate [Member]
Impaired loans by loan portfolio
Recorded Investment		6,213	9,552
Unpaid Principal Balance		12,101	9,832
Average Recorded Investment		12,595	10,561
Interest Income Recognized		523	519
Related Allowance		0	0
With No Related Allowance Recorded [Member] \| Small Business [Member]
Impaired loans by loan portfolio
Recorded Investment		469	358
Unpaid Principal Balance		484	439
Average Recorded Investment		471	401
Interest Income Recognized		22	14
Related Allowance		0	0
With No Related Allowance Recorded [Member] \| Residential Real Estate [Member]
Impaired loans by loan portfolio
Recorded Investment		4,976	4,518
Unpaid Principal Balance		5,123	4,686
Average Recorded Investment		5,045	4,597
Interest Income Recognized		222	212
Related Allowance		0	0
With No Related Allowance Recorded [Member] \| Home Equity [Member]
Impaired loans by loan portfolio
Recorded Investment		3,764	4,957
Unpaid Principal Balance		3,893	5,199
Average Recorded Investment		3,869	5,230
Interest Income Recognized		184	220
Related Allowance		0	0
With No Related Allowance Recorded [Member] \| Consumer Portfolio Segment [Member]
Impaired loans by loan portfolio
Recorded Investment		34	56
Unpaid Principal Balance		34	56
Average Recorded Investment		41	64
Interest Income Recognized		3	4
Related Allowance		0	0
With Allowance Recorded [Member]
Impaired loans by loan portfolio
Recorded Investment		10,386	11,160
Unpaid Principal Balance		11,535	12,389
Average Recorded Investment		10,605	11,552
Interest Income Recognized		447	443
With Allowance Recorded [Member] \| Commercial and Industrial [Member]
Impaired loans by loan portfolio
Recorded Investment		670	370
Unpaid Principal Balance		670	370
Average Recorded Investment		718	385
Interest Income Recognized		29	19
With Allowance Recorded [Member] \| Commercial Real Estate [Member]
Impaired loans by loan portfolio
Recorded Investment		2,124	1,287
Unpaid Principal Balance		2,124	1,287
Average Recorded Investment		2,176	1,311
Interest Income Recognized		122	74
With Allowance Recorded [Member] \| Small Business [Member]
Impaired loans by loan portfolio
Recorded Investment		68	183
Unpaid Principal Balance		105	223
Average Recorded Investment		74	225
Interest Income Recognized		2	13
With Allowance Recorded [Member] \| Residential Real Estate [Member]
Impaired loans by loan portfolio
Recorded Investment		6,252	8,188
Unpaid Principal Balance		7,163	9,217
Average Recorded Investment		6,326	8,459
Interest Income Recognized		239	289
With Allowance Recorded [Member] \| Home Equity [Member]
Impaired loans by loan portfolio
Recorded Investment		1,184	991
Unpaid Principal Balance		1,382	1,149
Average Recorded Investment		1,214	1,018
Interest Income Recognized		52	43
With Allowance Recorded [Member] \| Consumer Portfolio Segment [Member]
Impaired loans by loan portfolio
Recorded Investment		88	141
Unpaid Principal Balance		91	143
Average Recorded Investment		97	154
Interest Income Recognized		$ 3	$ 5

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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