Loans (Loan Portfolio) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	$ 3,609,791	$ 3,557,908
Net Deferred Loan (Fees) Costs	44,108	37,230
Loans, Net	3,653,899	3,595,138
Allowance for credit losses - loans	(45,444)	(52,420)
Total loans, net	3,608,455	3,542,718
Commercial Business [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	689,819	798,409
Net Deferred Loan (Fees) Costs	(3,628)	(4,261)
Loans, Net	686,191	794,148
Commercial Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	1,350,932	1,256,525
Net Deferred Loan (Fees) Costs	(2,382)	(2,624)
Loans, Net	1,348,550	1,253,901
Residential Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	570,435	586,537
Net Deferred Loan (Fees) Costs	13,656	13,263
Loans, Net	584,091	599,800
Residential Real Estate Lines [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	76,214	86,708
Net Deferred Loan (Fees) Costs	2,982	3,097
Loans, Net	79,196	89,805
Consumer Indirect [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	907,185	812,816
Net Deferred Loan (Fees) Costs	33,352	27,605
Loans, Net	940,537	840,421
Other Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	15,206	16,913
Net Deferred Loan (Fees) Costs	128	150
Loans, Net	$ 15,334	$ 17,063

Loans and leases receivable deferred loan (fees) costs.

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- Definition

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+ References

No definition available.

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- Definition

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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