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Allowance for Credit Losses and Credit Quality of Loans, Credit Quality by Loan Class (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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Credit Quality by Loan Class [Abstract] |  |
Net Loans | $ 7,498,885 | $ 7,136,098
Indirect Auto [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans | 931,286 | 1,193,635
Specialty Lending [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans | $ 579,644 | 542,063
Originated Loans [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 6,871,220
Originated Loans [Member] | Commercial Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 2,790,472
Originated Loans [Member] | Commercial Credit Exposure [Member] | Pass [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 2,651,441
Originated Loans [Member] | Commercial Credit Exposure [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 58,899
Originated Loans [Member] | Commercial Credit Exposure [Member] | Substandard [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 79,626
Originated Loans [Member] | Commercial Credit Exposure [Member] | Doubtful [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 506
Originated Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 840,906
Originated Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Pass [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 782,763
Originated Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 28,380
Originated Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Substandard [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 29,257
Originated Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Doubtful [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 506
Originated Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 1,949,566
Originated Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Pass [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 1,868,678
Originated Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 30,519
Originated Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Substandard [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 50,369
Originated Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Doubtful [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 0
Originated Loans [Member] | Business Banking Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 538,528
Originated Loans [Member] | Business Banking Credit Exposure [Member] | Non-classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 524,725
Originated Loans [Member] | Business Banking Credit Exposure [Member] | Classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 13,803
Originated Loans [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 538,528
Originated Loans [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] | Non-classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 524,725
Originated Loans [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] | Classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 13,803
Originated Loans [Member] | Consumer Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 2,222,943
Originated Loans [Member] | Consumer Credit Exposure [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 2,215,503
Originated Loans [Member] | Consumer Credit Exposure [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 7,440
Originated Loans [Member] | Consumer Credit Exposure [Member] | Indirect Auto [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 1,193,635
Originated Loans [Member] | Consumer Credit Exposure [Member] | Indirect Auto [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 1,190,455
Originated Loans [Member] | Consumer Credit Exposure [Member] | Indirect Auto [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 3,180
Originated Loans [Member] | Consumer Credit Exposure [Member] | Specialty Lending [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 542,063
Originated Loans [Member] | Consumer Credit Exposure [Member] | Specialty Lending [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 540,756
Originated Loans [Member] | Consumer Credit Exposure [Member] | Specialty Lending [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 1,307
Originated Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 487,245
Originated Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 484,292
Originated Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 2,953
Originated Loans [Member] | Residential Real Estate Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 1,319,277
Originated Loans [Member] | Residential Real Estate Credit Exposure [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 1,312,742
Originated Loans [Member] | Residential Real Estate Credit Exposure [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 6,535
Originated Loans [Member] | Residential Real Estate Credit Exposure [Member] | Residential Real Estate [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 1,319,277
Originated Loans [Member] | Residential Real Estate Credit Exposure [Member] | Residential Real Estate [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 1,312,742
Originated Loans [Member] | Residential Real Estate Credit Exposure [Member] | Residential Real Estate [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 6,535
Acquired Loans [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 264,878
Acquired Loans [Member] | Commercial Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 80,301
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Pass [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 78,346
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 1,269
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Substandard [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 686
Acquired Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 19,364
Acquired Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Pass [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 17,801
Acquired Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 1,269
Acquired Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Substandard [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 294
Acquired Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 60,937
Acquired Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Pass [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 60,545
Acquired Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 0
Acquired Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Substandard [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 392
Acquired Loans [Member] | Business Banking Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 34,965
Acquired Loans [Member] | Business Banking Credit Exposure [Member] | Non-classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 32,030
Acquired Loans [Member] | Business Banking Credit Exposure [Member] | Classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 2,935
Acquired Loans [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 34,965
Acquired Loans [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] | Non-classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 32,030
Acquired Loans [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] | Classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 2,935
Acquired Loans [Member] | Consumer Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 23,733
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 23,628
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 105
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 23,733
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 23,628
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 105
Acquired Loans [Member] | Residential Real Estate Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 125,879
Acquired Loans [Member] | Residential Real Estate Credit Exposure [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 124,509
Acquired Loans [Member] | Residential Real Estate Credit Exposure [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 1,370
Acquired Loans [Member] | Residential Real Estate Credit Exposure [Member] | Residential Real Estate [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 125,879
Acquired Loans [Member] | Residential Real Estate Credit Exposure [Member] | Residential Real Estate [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | 124,509
Acquired Loans [Member] | Residential Real Estate Credit Exposure [Member] | Residential Real Estate [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net Loans |  | $ 1,370

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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5074-111524 + Details
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