Loans and Allowance for Credit Losses (Impaired Financing Receivables by Loan Class) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	$ 6,679	$ 11,323
Recorded investment with no allowance	5,388	6,656
Recorded investment with an allowance	67	3,934
Related allowance	67	776
Quarter-to-date average recorded investment	6,429	10,886
Year-to-date average recorded investment	8,963	13,501
Impaired Accruing Restructured Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	6,997	7,501
Recorded investment with no allowance	5,130	5,372
Recorded investment with an allowance	1,867	2,129
Related allowance	146	199
Quarter-to-date average recorded investment	7,152	7,531
Year-to-date average recorded investment	7,306	7,699
Interest income recognized	267	306
Other Impaired Accruing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	804	1,326
Recorded investment with no allowance	804	1,326
Quarter-to-date average recorded investment	801	1,172
Year-to-date average recorded investment	1,183	732
Interest income recognized	7	10
Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	14,480	20,150
Recorded investment with no allowance	11,322	13,354
Recorded investment with an allowance	1,934	6,063
Related allowance	213	975
Quarter-to-date average recorded investment	14,382	19,589
Year-to-date average recorded investment	17,452	21,932
Interest income recognized	274	316
Residential Portfolio Segment [Member] | Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	1,665	2,660
Recorded investment with no allowance	1,585	678
Recorded investment with an allowance		1,797
Related allowance		215
Quarter-to-date average recorded investment	1,861	2,052
Year-to-date average recorded investment	2,648	2,691
Residential Portfolio Segment [Member] | Impaired Accruing Restructured Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	3,845	4,041
Recorded investment with no allowance	2,617	2,583
Recorded investment with an allowance	1,228	1,458
Related allowance	135	180
Quarter-to-date average recorded investment	3,857	4,052
Year-to-date average recorded investment	3,920	4,157
Interest income recognized	160	171
Residential Portfolio Segment [Member] | Other Impaired Accruing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	292	556
Recorded investment with no allowance	292	556
Quarter-to-date average recorded investment	269	786
Year-to-date average recorded investment	362	337
Interest income recognized	2	5
Residential Portfolio Segment [Member] | Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	5,802	7,257
Recorded investment with no allowance	4,494	3,817
Recorded investment with an allowance	1,228	3,255
Related allowance	135	395
Quarter-to-date average recorded investment	5,987	6,890
Year-to-date average recorded investment	6,930	7,185
Interest income recognized	162	176
Commercial Real Estate Portfolio Segment [Member] | Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	4,288	8,242
Recorded investment with no allowance	3,220	5,680
Recorded investment with an allowance	67	2,137
Related allowance	67	561
Quarter-to-date average recorded investment	3,971	8,533
Year-to-date average recorded investment	5,669	9,421
Commercial Real Estate Portfolio Segment [Member] | Impaired Accruing Restructured Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	3,118	3,419
Recorded investment with no allowance	2,479	2,748
Recorded investment with an allowance	639	671
Related allowance	11	19
Quarter-to-date average recorded investment	3,261	3,438
Year-to-date average recorded investment	3,349	3,496
Interest income recognized	104	125
Commercial Real Estate Portfolio Segment [Member] | Other Impaired Accruing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	512	770
Recorded investment with no allowance	512	770
Quarter-to-date average recorded investment	532	297
Year-to-date average recorded investment	774	336
Interest income recognized	5	4
Commercial Real Estate Portfolio Segment [Member] | Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	7,918	12,431
Recorded investment with no allowance	6,211	9,198
Recorded investment with an allowance	706	2,808
Related allowance	78	580
Quarter-to-date average recorded investment	7,764	12,268
Year-to-date average recorded investment	9,792	13,253
Interest income recognized	109	129
Commercial Portfolio Segment [Member] | Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	401	421
Recorded investment with no allowance	258	298
Quarter-to-date average recorded investment	272	301
Year-to-date average recorded investment	390	313
Commercial Portfolio Segment [Member] | Other Impaired Accruing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Quarter-to-date average recorded investment		89
Year-to-date average recorded investment	13	38
Interest income recognized		1
Commercial Portfolio Segment [Member] | Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	401	421
Recorded investment with no allowance	258	298
Quarter-to-date average recorded investment	272	390
Year-to-date average recorded investment	403	351
Interest income recognized		1
Consumer Portfolio Segment [Member] | Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	28
Recorded investment with no allowance	28
Quarter-to-date average recorded investment	28
Year-to-date average recorded investment	9
Consumer Portfolio Segment [Member] | Other Impaired Accruing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Year-to-date average recorded investment	9	3
Consumer Portfolio Segment [Member] | Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	28
Recorded investment with no allowance	28
Quarter-to-date average recorded investment	28
Year-to-date average recorded investment	18	3
Construction Loans [Member] | Commercial and Residential Real Estate Portfolio Segment [Member] | Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	297
Recorded investment with no allowance	297
Quarter-to-date average recorded investment	297
Year-to-date average recorded investment	247	1,076
Construction Loans [Member] | Commercial and Residential Real Estate Portfolio Segment [Member] | Impaired Accruing Restructured Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	34	41
Recorded investment with no allowance	34	41
Quarter-to-date average recorded investment	34	41
Year-to-date average recorded investment	37	46
Interest income recognized	3	10
Construction Loans [Member] | Commercial and Residential Real Estate Portfolio Segment [Member] | Other Impaired Accruing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Year-to-date average recorded investment	25	18
Construction Loans [Member] | Commercial and Residential Real Estate Portfolio Segment [Member] | Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	331	41
Recorded investment with no allowance	331	41
Quarter-to-date average recorded investment	331	41
Year-to-date average recorded investment	309	1,140
Interest income recognized	$ 3	$ 10