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Allowance for Credit Losses and Credit Quality of Loans, Credit Quality by Loan Class (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019
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Credit Quality by Loan Class [Abstract] |  |
Net loans | $ 7,560,643 | $ 7,136,098
Originated [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 6,871,220
Originated [Member] | Commercial Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 2,790,472
Originated [Member] | Commercial Credit Exposure [Member] | Pass [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 2,651,441
Originated [Member] | Commercial Credit Exposure [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 58,899
Originated [Member] | Commercial Credit Exposure [Member] | Substandard [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 79,626
Originated [Member] | Commercial Credit Exposure [Member] | Doubtful [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 506
Originated [Member] | Commercial Credit Exposure [Member] | C&I [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 840,906
Originated [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Pass [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 782,763
Originated [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 28,380
Originated [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Substandard [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 29,257
Originated [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Doubtful [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 506
Originated [Member] | Commercial Credit Exposure [Member] | CRE [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 1,949,566
Originated [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Pass [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 1,868,678
Originated [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 30,519
Originated [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Substandard [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 50,369
Originated [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Doubtful [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 0
Originated [Member] | Business Banking Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 538,528
Originated [Member] | Business Banking Credit Exposure [Member] | Non-classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 524,725
Originated [Member] | Business Banking Credit Exposure [Member] | Classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 13,803
Originated [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 538,528
Originated [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] | Non-classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 524,725
Originated [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] | Classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 13,803
Originated [Member] | Consumer Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 2,222,943
Originated [Member] | Consumer Credit Exposure [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 2,215,503
Originated [Member] | Consumer Credit Exposure [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 7,440
Originated [Member] | Consumer Credit Exposure [Member] | Indirect Auto [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 1,193,635
Originated [Member] | Consumer Credit Exposure [Member] | Indirect Auto [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 1,190,455
Originated [Member] | Consumer Credit Exposure [Member] | Indirect Auto [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 3,180
Originated [Member] | Consumer Credit Exposure [Member] | Specialty Lending [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 542,063
Originated [Member] | Consumer Credit Exposure [Member] | Specialty Lending [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 540,756
Originated [Member] | Consumer Credit Exposure [Member] | Specialty Lending [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 1,307
Originated [Member] | Consumer Credit Exposure [Member] | Direct [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 487,245
Originated [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 484,292
Originated [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 2,953
Originated [Member] | Residential Real Estate Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 1,319,277
Originated [Member] | Residential Real Estate Credit Exposure [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 1,312,742
Originated [Member] | Residential Real Estate Credit Exposure [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 6,535
Originated [Member] | Residential Real Estate Credit Exposure [Member] | Residential Real Estate [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 1,319,277
Originated [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 [Member] | Residential Real Estate Credit Exposure [Member] | Residential Real Estate [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 6,535
Acquired [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 264,878
Acquired [Member] | Commercial Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 80,301
Acquired [Member] | Commercial Credit Exposure [Member] | Pass [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 78,346
Acquired [Member] | Commercial Credit Exposure [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 1,269
Acquired [Member] | Commercial Credit Exposure [Member] | Substandard [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 686
Acquired [Member] | Commercial Credit Exposure [Member] | C&I [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 19,364
Acquired [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Pass [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 17,801
Acquired [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 1,269
Acquired [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Substandard [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 294
Acquired [Member] | Commercial Credit Exposure [Member] | CRE [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 60,937
Acquired [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Pass [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 60,545
Acquired [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 0
Acquired [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Substandard [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 392
Acquired [Member] | Business Banking Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 34,965
Acquired [Member] | Business Banking Credit Exposure [Member] | Non-classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 32,030
Acquired [Member] | Business Banking Credit Exposure [Member] | Classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 2,935
Acquired [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 34,965
Acquired [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] | Non-classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 32,030
Acquired [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] | Classified [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 2,935
Acquired [Member] | Consumer Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 23,733
Acquired [Member] | Consumer Credit Exposure [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 23,628
Acquired [Member] | Consumer Credit Exposure [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 105
Acquired [Member] | Consumer Credit Exposure [Member] | Direct [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 23,733
Acquired [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 23,628
Acquired [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 105
Acquired [Member] | Residential Real Estate Credit Exposure [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 125,879
Acquired [Member] | Residential Real Estate Credit Exposure [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 124,509
Acquired [Member] | Residential Real Estate Credit Exposure [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 1,370
Acquired [Member] | Residential Real Estate Credit Exposure [Member] | Residential Real Estate [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 125,879
Acquired [Member] | Residential Real Estate Credit Exposure [Member] | Residential Real Estate [Member] | Performing [Member] |  |
Credit Quality by Loan Class [Abstract] |  |
Net loans |  | 124,509
Acquired [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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