Allowance for Credit Losses on Loans (Allowance for Loan Losses Rollforward Analysis) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	$ 38,027	$ 39,088
Charge-offs	(61)	(36)
Recoveries	14	184
Provision	800	0
Allowance, Ending Balance	38,780	39,236
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	18,435	18,933
Charge-offs	0	0
Recoveries	0	145
Provision	2,939	(618)
Allowance, Ending Balance	21,374	18,460
Commercial & Industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	10,356	10,832
Charge-offs	(11)	(5)
Recoveries	5	6
Provision	(517)	389
Allowance, Ending Balance	9,833	11,222
Total Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	28,791	29,765
Charge-offs	(11)	(5)
Recoveries	5	151
Provision	2,422	(229)
Allowance, Ending Balance	31,207	29,682
Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	7,740	7,860
Charge-offs	0	0
Recoveries	0	21
Provision	(1,501)	185
Allowance, Ending Balance	6,239	8,066
Home Equity
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	1,115	1,069
Charge-offs	0	0
Recoveries	1	2
Provision	(138)	27
Allowance, Ending Balance	978	1,098
Other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	381	394
Charge-offs	(50)	(31)
Recoveries	8	10
Provision	17	17
Allowance, Ending Balance	356	390
Total Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	1,496	1,463
Charge-offs	(50)	(31)
Recoveries	9	12
Provision	(121)	44
Allowance, Ending Balance	$ 1,334	$ 1,488

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (4)

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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 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.

+ References

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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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