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Loans (Loan Portfolio) (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | $ 3,195,175 | $ 3,179,465
Net Deferred Loan (Fees) Costs | 42,052 | 41,522
Loans, Net | 3,237,227 | 3,220,987
Allowance for credit losses - loans | (43,356) | (30,482)
Total loans, net | 3,193,871 | 3,190,505
Commercial Business [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 587,903 | 571,222
Net Deferred Loan (Fees) Costs | 965 | 818
Loans, Net | 588,868 | 572,040
Allowance for credit losses - loans |  | (11,358)
Commercial Mortgage [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 1,109,344 | 1,108,315
Net Deferred Loan (Fees) Costs | (1,968) | (2,032)
Loans, Net | 1,107,376 | 1,106,283
Allowance for credit losses - loans |  | (5,681)
Residential Real Estate Loans [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 567,714 | 560,717
Net Deferred Loan (Fees) Costs | 12,086 | 11,633
Loans, Net | 579,800 | 572,350
Allowance for credit losses - loans |  | (1,059)
Residential Real Estate Lines [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 98,996 | 101,048
Net Deferred Loan (Fees) Costs | 3,117 | 3,070
Loans, Net | 102,113 | 104,118
Allowance for credit losses - loans |  | (118)
Consumer Indirect [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 815,969 | 822,179
Net Deferred Loan (Fees) Costs | 27,699 | 27,873
Loans, Net | 843,668 | 850,052
Allowance for credit losses - loans |  | (11,852)
Other Consumer [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 15,249 | 15,984
Net Deferred Loan (Fees) Costs | 153 | 160
Loans, Net | $ 15,402 | 16,144
Allowance for credit losses - loans |  | $ (414)

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