Loans and Allowance for Credit Losses (Impaired Financing Receivables by Loan Class) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	$ 13,759		$ 14,480
Recorded investment with no allowance	11,393		11,322
Recorded investment with an allowance	1,131		1,934
Related allowance	95		213
Quarter-to-date average recorded investment	13,040	$ 18,172
Interest income recognized	69	63
Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	6,115		6,679
Recorded investment with no allowance	4,880		5,388
Recorded investment with an allowance			67
Related allowance			67
Quarter-to-date average recorded investment	4,999	10,704
Impaired Accruing Restructured Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	6,456		6,997
Recorded investment with no allowance	5,325		5,130
Recorded investment with an allowance	1,131		1,867
Related allowance	95		146
Quarter-to-date average recorded investment	6,628	7,468
Interest income recognized	63	63
Other Impaired Accruing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	1,188		804
Recorded investment with no allowance	1,188		804
Quarter-to-date average recorded investment	1,413
Interest income recognized	6
Residential Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	5,368		5,802
Recorded investment with no allowance	4,150		4,494
Recorded investment with an allowance	1,131		1,228
Related allowance	95		135
Quarter-to-date average recorded investment	5,794	6,894
Interest income recognized	45	38
Residential Portfolio Segment [Member] | Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	1,309		1,665
Recorded investment with no allowance	1,222		1,585
Quarter-to-date average recorded investment	1,411	2,871
Residential Portfolio Segment [Member] | Impaired Accruing Restructured Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	3,381		3,845
Recorded investment with no allowance	2,250		2,617
Recorded investment with an allowance	1,131		1,228
Related allowance	95		135
Quarter-to-date average recorded investment	3,530	4,023
Interest income recognized	40	38
Residential Portfolio Segment [Member] | Other Impaired Accruing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	678		292
Recorded investment with no allowance	678		292
Quarter-to-date average recorded investment	853
Interest income recognized	5
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	7,638		7,918
Recorded investment with no allowance	6,638		6,211
Recorded investment with an allowance			706
Related allowance			78
Quarter-to-date average recorded investment	6,587	10,758
Interest income recognized	24	24
Commercial Real Estate Portfolio Segment [Member] | Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	4,085		4,288
Recorded investment with no allowance	3,085		3,220
Recorded investment with an allowance			67
Related allowance			67
Quarter-to-date average recorded investment	3,012	7,352
Commercial Real Estate Portfolio Segment [Member] | Impaired Accruing Restructured Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	3,043		3,118
Recorded investment with no allowance	3,043		2,479
Recorded investment with an allowance			639
Related allowance			11
Quarter-to-date average recorded investment	3,065	3,406
Interest income recognized	23	24
Commercial Real Estate Portfolio Segment [Member] | Other Impaired Accruing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	510		512
Recorded investment with no allowance	510		512
Quarter-to-date average recorded investment	510
Interest income recognized	1
Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	396		401
Recorded investment with no allowance	248		258
Quarter-to-date average recorded investment	301	382
Commercial Portfolio Segment [Member] | Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	396		401
Recorded investment with no allowance	248		258
Quarter-to-date average recorded investment	251	382
Commercial Portfolio Segment [Member] | Other Impaired Accruing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Quarter-to-date average recorded investment	50
Consumer Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	28		28
Recorded investment with no allowance	28		28
Quarter-to-date average recorded investment	28
Consumer Portfolio Segment [Member] | Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	28		28
Recorded investment with no allowance	28		28
Quarter-to-date average recorded investment	28
Construction Loans [Member] | Commercial and Residential Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	329		331
Recorded investment with no allowance	329		331
Quarter-to-date average recorded investment	330	138
Interest income recognized		1
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		297
Recorded investment with no allowance	297		297
Quarter-to-date average recorded investment	297	99
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	32		34
Recorded investment with no allowance	32		$ 34
Quarter-to-date average recorded investment	$ 33	39
Interest income recognized		$ 1