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Loans and Allowance for Credit Losses - Allowance for Credit Loss Activity (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period | $ 107,966 | $ 101,340 | $ 101,340
Provision for credit losses on loans | 3,425 | 1,090 |
Charge-offs | (6,939) | (4,459) | (24,638)
Recoveries | 350 | 9,574 |
Net Recoveries/(Charge-offs) | (6,589) | 5,115 |
Balance at End of Period | 104,802 | 108,113 | 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 | 37,886 | 41,428 | 41,428
Provision for credit losses on loans | 2,838 | (1,011) |
Charge-offs | (5,205) | 0 | (1,706)
Recoveries | 93 | 9 |
Net Recoveries/(Charge-offs) | (5,112) | 9 |
Balance at End of Period | 35,612 | 40,426 | 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 | 34,538 | 25,710 | 25,710
Provision for credit losses on loans | 680 | (476) |
Charge-offs | (1,128) | (3,412) | (19,254)
Recoveries | 117 | 9,400 |
Net Recoveries/(Charge-offs) | (1,011) | 5,988 |
Balance at End of Period | 34,207 | 31,297 | 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 | 5,382 | 6,264 | 6,264
Provision for credit losses on loans | (233) | 412 |
Charge-offs | 0 | 0 | (451)
Recoveries | 0 | 2 |
Net Recoveries/(Charge-offs) | 0 | 2 |
Balance at End of Period | 5,149 | 6,893 | 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 | 12,858 | 12,547 | 12,547
Provision for credit losses on loans | (995) | 1,497 |
Charge-offs | (98) | (652) | (1,306)
Recoveries | 33 | 37 |
Net Recoveries/(Charge-offs) | (65) | (615) |
Balance at End of Period | 11,798 | 13,680 | 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 | 14,663 | 12,105 | 12,105
Provision for credit losses on loans | 859 | 488 |
Charge-offs | (139) | (77) | (421)
Recoveries | 27 | 61 |
Net Recoveries/(Charge-offs) | (112) | (16) |
Balance at End of Period | 15,410 | 12,855 | 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 | 2,639 | 3,286 | 3,286
Provision for credit losses on loans | 276 | 180 |
Charge-offs | (369) | (318) | (1,500)
Recoveries | 80 | 65 |
Net Recoveries/(Charge-offs) | (289) | (253) |
Balance at End of Period | $ 2,626 | 2,962 | 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)

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- 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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