Allowance for Credit Losses on Loans (Allowance for Credit Losses on Loans Rollforward Analysis) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	$ 27,014	$ 27,072	$ 26,488
Charge-offs	(1,317)	(2,020)	(1,187)
Recoveries	172	387	221
Provision	11,736	1,575	1,550
Ending Balance	44,106	27,014	27,072
Adoption of ASC 326				$ 6,501
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	14,741	15,381	12,729
Charge-offs	(356)	(1,028)	(627)
Recoveries	51	125	25
Provision	4,224	263	3,254
Ending Balance	22,065	14,741	15,381
Adoption of ASC 326				3,405
Commercial & Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	3,921	5,847	5,580
Charge-offs	(586)	(21)	(10)
Recoveries	24	168	119
Provision	5,840	(2,073)	158
Ending Balance	12,228	3,921	5,847
Adoption of ASC 326				3,029
Total Commercial [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	18,662	21,228	18,309
Charge-offs	(942)	(1,049)	(637)
Recoveries	75	293	144
Provision	10,064	(1,810)	3,412
Ending Balance	34,293	18,662	21,228
Adoption of ASC 326				6,434
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	6,615	3,987	5,427
Charge-offs	(99)	(486)	(250)
Recoveries	20	0	21
Provision	1,285	3,114	(1,211)
Ending Balance	8,042	6,615	3,987
Adoption of ASC 326				221
Home Equity [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	1,390	1,603	2,412
Charge-offs	(224)	(390)	(193)
Recoveries	52	72	29
Provision	188	105	(645)
Ending Balance	1,300	1,390	1,603
Adoption of ASC 326				(106)
Other Consumer [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	347	254	340
Charge-offs	(52)	(95)	(107)
Recoveries	25	22	27
Provision	199	166	(6)
Ending Balance	471	347	254
Adoption of ASC 326				(48)
Total Consumer [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	1,737	1,857	2,752
Charge-offs	(276)	(485)	(300)
Recoveries	77	94	56
Provision	387	271	(651)
Ending Balance	$ 1,771	$ 1,737	$ 1,857
Adoption of ASC 326				$ (154)

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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