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Loans (Loan Portfolio) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	$ 3,591,839	$ 3,557,908
Net Deferred Loan (Fees) Costs	40,329	37,230
Loans, Net	3,632,168	3,595,138
Allowance for credit losses - loans	(46,365)	(52,420)
Total loans, net	3,585,803	3,542,718
Commercial Business [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	735,928	798,409
Net Deferred Loan (Fees) Costs	(4,720)	(4,261)
Loans, Net	731,208	794,148
Commercial Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	1,317,754	1,256,525
Net Deferred Loan (Fees) Costs	(2,350)	(2,624)
Loans, Net	1,315,404	1,253,901
Residential Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	576,632	586,537
Net Deferred Loan (Fees) Costs	13,671	13,263
Loans, Net	590,303	599,800
Residential Real Estate Lines [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	77,773	86,708
Net Deferred Loan (Fees) Costs	3,008	3,097
Loans, Net	80,781	89,805
Consumer Indirect [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	868,430	812,816
Net Deferred Loan (Fees) Costs	30,588	27,605
Loans, Net	899,018	840,421
Other Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	15,322	16,913
Net Deferred Loan (Fees) Costs	132	150
Loans, Net	$ 15,454	$ 17,063

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Loans and leases receivable deferred loan (fees) costs.

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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 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.

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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.

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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.

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