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Loans (Loan Portfolio) (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | --- | --- | --- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total Loans | $ 4,461,468 |  | $ 4,462,139 |  |  |
Principal Amount Outstanding, Total | 4,419,114 |  | 4,416,251 |  |  |
Net Deferred Loan (Fees) Costs | 42,354 |  | 45,888 |  |  |
Total loans, net | 4,417,516 |  | 4,411,057 |  |  |
Allowance for credit losses - loans | (43,952) | $ (43,075) | (51,082) | $ (49,836) | $ (47,528) | $ (45,413)
Commercial Business [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total Loans | 713,947 |  | 735,700 |  |  |
Principal Amount Outstanding, Total | 713,192 |  | 734,947 |  |  |
Net Deferred Loan (Fees) Costs | 755 |  | 753 |  |  |
Allowance for credit losses - loans | (12,246) | (12,991) | (13,102) | (13,418) | (12,911) | (12,585)
Commercial Mortgage [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total Loans | 2,085,870 |  | 2,005,319 |  |  |
Principal Amount Outstanding, Total | 2,089,018 |  | 2,009,269 |  |  |
Net Deferred Loan (Fees) Costs | (3,148) |  | (3,950) |  |  |
Allowance for credit losses - loans | (15,365) | (14,113) | (15,858) | (16,826) | (15,195) | (14,412)
Residential Real Estate Loans [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total Loans | 647,675 |  | 649,822 |  |  |
Principal Amount Outstanding, Total | 635,717 |  | 637,173 |  |  |
Net Deferred Loan (Fees) Costs | 11,958 |  | 12,649 |  |  |
Allowance for credit losses - loans | (4,211) | (4,630) | (5,286) | (4,646) | (4,213) | (3,301)
Residential Real Estate Lines [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total Loans | 75,510 |  | 77,367 |  |  |
Principal Amount Outstanding, Total | 72,182 |  | 73,972 |  |  |
Net Deferred Loan (Fees) Costs | 3,328 |  | 3,395 |  |  |
Allowance for credit losses - loans | (769) | (794) | (764) | (710) | (651) | (608)
Consumer Indirect [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total Loans | 894,596 |  | 948,831 |  |  |
Principal Amount Outstanding, Total | 865,066 |  | 915,723 |  |  |
Net Deferred Loan (Fees) Costs | 29,530 |  | 33,108 |  |  |
Allowance for credit losses - loans | (10,842) | (9,854) | (14,099) | (13,306) | (14,117) | (14,238)
Other Consumer [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total Loans | 43,870 |  | 45,100 |  |  |
Principal Amount Outstanding, Total | 43,939 |  | 45,167 |  |  |
Net Deferred Loan (Fees) Costs | (69) |  | (67) |  |  |
Allowance for credit losses - loans | $ (519) | $ (693) | $ (1,973) | $ (930) | $ (441) | $ (269)

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