Loans and Allowance for Credit Losses on Loans (Activity in Allowance for Credit Losses on Loans by Portfolio Segment) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	$ 25,171	$ 24,712	$ 24,171
Loans charged off	(1,838)	(2,713)	(2,248)
Recoveries	1,084	310	1,944
Provision (credit)	13,215	2,862	845
Ending balance	37,865	25,171	24,712
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	233
Ending balance		233
Commercial real estate, non owner-occupied
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	10,924
Loans charged off	(82)
Recoveries	107
Provision (credit)	11,497
Ending balance	21,778	10,924
Commercial real estate, non owner-occupied \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	(668)
Ending balance		(668)
Commercial real estate, owner-occupied
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	1,490
Loans charged off	(21)
Recoveries	13
Provision (credit)	1,440
Ending balance	2,832	1,490
Commercial real estate, owner-occupied \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	(90)
Ending balance		(90)
Commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	3,985	3,957	4,622
Loans charged off	(1,130)	(1,238)	(991)
Recoveries	572	225	1,771
Provision (credit)	1,728	1,041	(1,445)
Ending balance	6,703	3,985	3,957
Commercial \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	1,548
Ending balance		1,548
SBA PPP Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Loans charged off	0
Recoveries	0
Provision (credit)	69
Ending balance	69
SBA PPP Portfolio Segment \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	0
Ending balance		0
Residential real estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	5,842	6,071	5,086
Loans charged off	(121)	(462)	(173)
Recoveries	292	16	90
Provision (credit)	(1,410)	217	1,068
Ending balance	3,474	5,842	6,071
Residential real estate \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	(1,129)
Ending balance		(1,129)
Home equity
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	2,423	2,796	2,367
Loans charged off	(317)	(412)	(476)
Recoveries	33	1	44
Provision (credit)	(315)	38	861
Ending balance	2,616	2,423	2,796
Home equity \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	792
Ending balance		792
Consumer
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	507	234	233
Loans charged off	(167)	(301)	(96)
Recoveries	67	19	11
Provision (credit)	206	555	86
Ending balance	393	507	$ 234
Consumer \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	$ (220)
Ending balance		$ (220)

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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