Loans and Allowance for Credit Losses (Impaired Financing Receivables by Loan Class) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	$ 11,323	$ 17,974
Recorded investment with no allowance	6,656	12,039
Recorded investment with an allowance	3,934	4,616
Related allowance	776	541
Quarter-to-date average recorded investment	10,886	10,364
Year-to-date average recorded investment	13,501	7,357
Impaired Accruing Restructured Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	7,501	8,663
Recorded investment with no allowance	5,372	2,777
Recorded investment with an allowance	2,129	5,886
Related allowance	199	220
Quarter-to-date average recorded investment	7,531	8,801
Year-to-date average recorded investment	7,699	9,888
Interest income recognized	306	309
Other Impaired Accruing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	1,326
Recorded investment with no allowance	1,326
Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	20,150	26,637
Recorded investment with no allowance	13,354	14,816
Recorded investment with an allowance	6,063	10,502
Related allowance	975	761
Quarter-to-date average recorded investment	18,417	19,165
Year-to-date average recorded investment	21,200	17,245
Interest income recognized	306	309
Residential Portfolio Segment [Member] | Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	2,660	4,281
Recorded investment with no allowance	678	2,605
Recorded investment with an allowance	1,797	1,494
Related allowance	215	118
Quarter-to-date average recorded investment	2,052	2,820
Year-to-date average recorded investment	2,691	1,884
Residential Portfolio Segment [Member] | Impaired Accruing Restructured Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	4,041	4,454
Recorded investment with no allowance	2,583	1,440
Recorded investment with an allowance	1,458	3,014
Related allowance	180	183
Quarter-to-date average recorded investment	4,052	4,585
Year-to-date average recorded investment	4,157	4,606
Interest income recognized	171	125
Residential Portfolio Segment [Member] | Other Impaired Accruing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	556
Recorded investment with no allowance	556
Residential Portfolio Segment [Member] | Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	7,257	8,735
Recorded investment with no allowance	3,817	4,045
Recorded investment with an allowance	3,255	4,508
Related allowance	395	301
Quarter-to-date average recorded investment	6,104	7,405
Year-to-date average recorded investment	6,848	6,490
Interest income recognized	171	125
Commercial Real Estate Portfolio Segment [Member] | Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	8,242	10,029
Recorded investment with no allowance	5,680	9,307
Recorded investment with an allowance	2,137	67
Related allowance	561	67
Quarter-to-date average recorded investment	8,533	4,283
Year-to-date average recorded investment	9,421	2,149
Commercial Real Estate Portfolio Segment [Member] | Impaired Accruing Restructured Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	3,419	4,158
Recorded investment with no allowance	2,748	1,286
Recorded investment with an allowance	671	2,872
Related allowance	19	37
Quarter-to-date average recorded investment	3,438	4,164
Year-to-date average recorded investment	3,496	4,416
Interest income recognized	125	149
Commercial Real Estate Portfolio Segment [Member] | Other Impaired Accruing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	770
Recorded investment with no allowance	770
Commercial Real Estate Portfolio Segment [Member] | Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	12,431	14,187
Recorded investment with no allowance	9,198	10,593
Recorded investment with an allowance	2,808	2,939
Related allowance	580	104
Quarter-to-date average recorded investment	11,971	8,447
Year-to-date average recorded investment	12,917	6,565
Interest income recognized	125	149
Commercial Portfolio Segment [Member] | Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	421	445
Recorded investment with no allowance	298
Recorded investment with an allowance		340
Related allowance		36
Quarter-to-date average recorded investment	301	329
Year-to-date average recorded investment	313	336
Commercial Portfolio Segment [Member] | Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Unpaid principal balance	421	445
Recorded investment with no allowance	298
Recorded investment with an allowance		340
Related allowance		36
Quarter-to-date average recorded investment	301	329
Year-to-date average recorded investment	313	336
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		3,219
Recorded investment with no allowance		127
Recorded investment with an allowance		2,715
Related allowance		320
Quarter-to-date average recorded investment		2,932
Year-to-date average recorded investment	1,076	2,988
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	41	51
Recorded investment with no allowance	41	51
Quarter-to-date average recorded investment	41	52
Year-to-date average recorded investment	46	866
Interest income recognized	10	35
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	41	3,270
Recorded investment with no allowance	41	178
Recorded investment with an allowance		2,715
Related allowance		320
Quarter-to-date average recorded investment	41	2,984
Year-to-date average recorded investment	1,122	3,854
Interest income recognized	$ 10	$ 35