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Loans and Allowance for Credit Losses - Allowance for Credit Loss Activity (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period | $ 106,150 | $ 105,757 | $ 107,966 | $ 101,340 | $ 101,340
Provision for credit losses on loans | 308 | 6,159 | 4,693 | 15,860 |
Charge-offs | (2,440) | (4,077) | (10,223) | (20,758) | (24,638)
Recoveries | 303 | 367 | 1,885 | 11,196 |
Net Recoveries/(Charge-offs) | (2,137) | (3,710) | (8,338) | (9,562) |
Balance at End of Period | 104,321 | 108,206 | 104,321 | 108,206 | 107,966
Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period |  |  |  | 568 | 568
Commercial Loans | Commercial real estate |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period | 37,077 | 40,837 | 37,886 | 41,428 | 41,428
Provision for credit losses on loans | (1,441) | (1,081) | 2,498 | (2,636) |
Charge-offs | 0 | 0 | (5,205) | 0 | (1,706)
Recoveries | 1 | 1 | 458 | 965 |
Net Recoveries/(Charge-offs) | 1 | 1 | (4,747) | 965 |
Balance at End of Period | 35,637 | 39,757 | 35,637 | 39,757 | 37,886
Commercial Loans | Commercial real estate | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period |  |  |  | 0 | 0
Commercial Loans | Commercial and industrial |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period | 34,735 | 28,328 | 34,538 | 25,710 | 25,710
Provision for credit losses on loans | 2,184 | 6,068 | 2,715 | 14,424 |
Charge-offs | (1,308) | (3,033) | (2,436) | (18,253) | (19,254)
Recoveries | 113 | 161 | 907 | 9,568 |
Net Recoveries/(Charge-offs) | (1,195) | (2,872) | (1,529) | (8,685) |
Balance at End of Period | 35,724 | 31,524 | 35,724 | 31,524 | 34,538
Commercial Loans | Commercial and industrial | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period |  |  |  | 75 | 75
Commercial Loans | Commercial construction |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period | 5,347 | 6,739 | 5,382 | 6,264 | 6,264
Provision for credit losses on loans | (945) | 93 | (980) | 351 |
Charge-offs | 0 | 0 | 0 | 0 | (451)
Recoveries | 0 | 0 | 0 | 2 |
Net Recoveries/(Charge-offs) | 0 | 0 | 0 | 2 |
Balance at End of Period | 4,402 | 6,832 | 4,402 | 6,832 | 5,382
Commercial Loans | Commercial construction | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period |  |  |  | 215 | 215
Commercial Loans | Business banking |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period | 10,883 | 13,616 | 12,858 | 12,547 | 12,547
Provision for credit losses on loans | 252 | (15) | (1,610) | 1,325 |
Charge-offs | (179) | (590) | (373) | (1,252) | (1,306)
Recoveries | 73 | 90 | 154 | 230 |
Net Recoveries/(Charge-offs) | (106) | (500) | (219) | (1,022) |
Balance at End of Period | 11,029 | 13,101 | 11,029 | 13,101 | 12,858
Commercial Loans | Business banking | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period |  |  |  | 251 | 251
Consumer Loans | Consumer real estate |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period | 15,376 | 13,418 | 14,663 | 12,105 | 12,105
Provision for credit losses on loans | 46 | 896 | 1,136 | 1,934 |
Charge-offs | (616) | (107) | (1,087) | (224) | (421)
Recoveries | 40 | 42 | 134 | 156 |
Net Recoveries/(Charge-offs) | (576) | (65) | (953) | (68) |
Balance at End of Period | 14,846 | 14,249 | 14,846 | 14,249 | 14,663
Consumer Loans | Consumer real estate | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period |  |  |  | 278 | 278
Consumer Loans | Other consumer |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period | 2,732 | 2,819 | 2,639 | 3,286 | 3,286
Provision for credit losses on loans | 212 | 198 | 934 | 462 |
Charge-offs | (337) | (347) | (1,122) | (1,029) | (1,500)
Recoveries | 76 | 73 | 232 | 275 |
Net Recoveries/(Charge-offs) | (261) | (274) | (890) | (754) |
Balance at End of Period | $ 2,683 | $ 2,743 | $ 2,683 | 2,743 | 2,639
Consumer Loans | Other consumer | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |
Balance at beginning of period |  |  |  | $ (251) | $ (251)

X
- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 + Details
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- Definition Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
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