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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

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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 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=122038336&loc=d3e74567-122707 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 + Details
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