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Loans (Loan Portfolio) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	$ 3,114,733	$ 3,044,320
Net Deferred Loan (Fees) Costs	41,687	42,278
Loans, Net	3,156,420	3,086,598
Allowance for loan losses	(31,668)	(33,914)
Total loans, net	3,124,752	3,052,684
Commercial Business [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	573,610	557,040
Net Deferred Loan (Fees) Costs	845	821
Loans, Net	574,455	557,861
Commercial Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	1,037,304	960,265
Net Deferred Loan (Fees) Costs	(1,854)	(2,071)
Loans, Net	1,035,450	958,194
Residential Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	547,839	514,981
Net Deferred Loan (Fees) Costs	10,817	9,174
Loans, Net	558,656	524,155
Residential Real Estate Lines [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	104,545	106,712
Net Deferred Loan (Fees) Costs	3,070	3,006
Loans, Net	107,615	109,718
Consumer Indirect [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	834,968	888,732
Net Deferred Loan (Fees) Costs	28,646	31,185
Loans, Net	863,614	919,917
Other Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal Amount Outstanding	16,467	16,590
Net Deferred Loan (Fees) Costs	163	163
Loans, Net	$ 16,630	$ 16,753

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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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-SubTopic 210
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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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