Allowance for Credit Losses on Loans (Allowance for Loan Losses Rollforward Analysis) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	$ 39,088	$ 44,106
Charge-offs	(36)	(64)
Recoveries	184	46
Provision	0	(1,951)
Allowance, Ending Balance	39,236	42,137
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	18,933	22,065
Charge-offs	0	0
Recoveries	145	0
Provision	(618)	(768)
Allowance, Ending Balance	18,460	21,297
Commercial & Industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	10,832	12,228
Charge-offs	(5)	(3)
Recoveries	6	2
Provision	389	162
Allowance, Ending Balance	11,222	12,389
Total Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	29,765	34,293
Charge-offs	(5)	(3)
Recoveries	151	2
Provision	(229)	(606)
Allowance, Ending Balance	29,682	33,686
Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	7,860	8,042
Charge-offs	0	(50)
Recoveries	21	33
Provision	185	(1,556)
Allowance, Ending Balance	8,066	6,469
Home Equity
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	1,069	1,300
Charge-offs	0	0
Recoveries	2	2
Provision	27	129
Allowance, Ending Balance	1,098	1,431
Other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	394	471
Charge-offs	(31)	(11)
Recoveries	10	9
Provision	17	82
Allowance, Ending Balance	390	551
Total Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	1,463	1,771
Charge-offs	(31)	(11)
Recoveries	12	11
Provision	44	211
Allowance, Ending Balance	$ 1,488	$ 1,982