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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
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period | $ 105,757 | $ 98,085 | $ 101,340 | $ 98,576
Provision for credit losses on loans | 6,159 | 2,309 | 15,860 | 2,804
Charge-offs | (4,077) | (1,239) | (20,758) | (9,899)
Recoveries | 367 | 529 | 11,196 | 8,213
Net (Charge-offs)/Recoveries | (3,710) | (710) | (9,562) | (1,686)
Balance at End of Period | 108,206 | 99,694 | 108,206 | 99,694
Impact of adopting ASU 2022-02 |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period |  |  | 568 |
Commercial Loans | Commercial real estate |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period | 40,837 | 45,314 | 41,428 | 50,700
Provision for credit losses on loans | (1,081) | (2,997) | (2,636) | (8,471)
Charge-offs | 0 | (628) | 0 | (827)
Recoveries | 1 | 145 | 965 | 432
Net (Charge-offs)/Recoveries | 1 | (483) | 965 | (395)
Balance at End of Period | 39,757 | 41,834 | 39,757 | 41,834
Commercial Loans | Commercial real estate | Impact of adopting ASU 2022-02 |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period |  |  | 0 |
Commercial Loans | Commercial and industrial |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period | 28,328 | 21,516 | 25,710 | 19,727
Provision for credit losses on loans | 6,068 | 3,806 | 14,424 | 4,573
Charge-offs | (3,033) | 0 | (18,253) | (5,797)
Recoveries | 161 | 6 | 9,568 | 6,835
Net (Charge-offs)/Recoveries | (2,872) | 6 | (8,685) | 1,038
Balance at End of Period | 31,524 | 25,338 | 31,524 | 25,338
Commercial Loans | Commercial and industrial | Impact of adopting ASU 2022-02 |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period |  |  | 75 |
Commercial Loans | Commercial construction |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period | 6,739 | 6,583 | 6,264 | 5,355
Provision for credit losses on loans | 93 | (1,159) | 351 | 68
Charge-offs | 0 | 0 | 0 | 0
Recoveries | 0 | 0 | 2 | 1
Net (Charge-offs)/Recoveries | 0 | 0 | 2 | 1
Balance at End of Period | 6,832 | 5,424 | 6,832 | 5,424
Commercial Loans | Commercial construction | Impact of adopting ASU 2022-02 |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period |  |  | 215 |
Commercial Loans | Business banking |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period | 13,616 | 12,157 | 12,547 | 11,338
Provision for credit losses on loans | (15) | 950 | 1,325 | 3,158
Charge-offs | (590) | (178) | (1,252) | (1,924)
Recoveries | 90 | 242 | 230 | 599
Net (Charge-offs)/Recoveries | (500) | 64 | (1,022) | (1,325)
Balance at End of Period | 13,101 | 13,171 | 13,101 | 13,171
Commercial Loans | Business banking | Impact of adopting ASU 2022-02 |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period |  |  | 251 |
Consumer Loans | Consumer real estate |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period | 13,418 | 9,673 | 12,105 | 8,733
Provision for credit losses on loans | 896 | 1,075 | 1,934 | 2,083
Charge-offs | (107) | (161) | (224) | (299)
Recoveries | 42 | 39 | 156 | 109
Net (Charge-offs)/Recoveries | (65) | (122) | (68) | (190)
Balance at End of Period | 14,249 | 10,626 | 14,249 | 10,626
Consumer Loans | Consumer real estate | Impact of adopting ASU 2022-02 |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period |  |  | 278 |
Consumer Loans | Other consumer |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period | 2,819 | 2,842 | 3,286 | 2,723
Provision for credit losses on loans | 198 | 634 | 462 | 1,393
Charge-offs | (347) | (272) | (1,029) | (1,052)
Recoveries | 73 | 97 | 275 | 237
Net (Charge-offs)/Recoveries | (274) | (175) | (754) | (815)
Balance at End of Period | $ 2,743 | $ 3,301 | 2,743 | $ 3,301
Consumer Loans | Other consumer | Impact of adopting ASU 2022-02 |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period |  |  | $ (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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