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Loans and Allowance for Credit Losses - Age Analysis of Past Due Loans Segregated by Class of Loans (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | --- | ---
Financing Receivable, Past Due [Line Items] |  |  |
Total | $ 7,836,349 | $ 7,742,958 |
Nonaccrual | 22,339 | 27,937 | $ 22,947
Current |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 7,792,113 | 7,703,543 |
Total Past Due Loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 44,236 | 39,415 |
30-59 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 20,025 | 5,431 |
60-89 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,872 | 6,047 |
Commercial Loans | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,776,065 | 2,708,531 |
Nonaccrual | 2,264 | 3,228 | 6,320
Commercial Loans | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,331,091 | 1,351,637 |
Nonaccrual | 5,385 | 11,173 | 878
Commercial Loans | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 367,869 | 341,266 |
Nonaccrual | 1,006 | 0 | 4,960
Commercial Loans | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,314,482 | 1,303,258 |
Nonaccrual | 3,172 | 2,988 | 4,147
Commercial Loans | Current | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,762,834 | 2,705,303 |
Commercial Loans | Current | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,325,706 | 1,338,053 |
Commercial Loans | Current | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 365,994 | 340,230 |
Commercial Loans | Current | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,308,969 | 1,297,651 |
Commercial Loans | Total Past Due Loans | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 13,231 | 3,228 |
Commercial Loans | Total Past Due Loans | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 5,385 | 13,584 |
Commercial Loans | Total Past Due Loans | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,875 | 1,036 |
Commercial Loans | Total Past Due Loans | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 5,513 | 5,607 |
Commercial Loans | 30-59 Days Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 10,967 | 0 |
Commercial Loans | 30-59 Days Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 415 |
Commercial Loans | 30-59 Days Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 869 | 0 |
Commercial Loans | 30-59 Days Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,596 | 2,336 |
Commercial Loans | 60-89 Days Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 0 |
Commercial Loans | 60-89 Days Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 1,996 |
Commercial Loans | 60-89 Days Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 1,036 |
Commercial Loans | 60-89 Days Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 745 | 283 |
Consumer Loans | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,948,677 | 1,933,509 |
Nonaccrual | 10,294 | 10,318 | 6,312
Consumer Loans | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 98,165 | 104,757 |
Nonaccrual | 218 | 230 | $ 330
Consumer Loans | Current | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,931,861 | 1,918,150 |
Consumer Loans | Current | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 96,749 | 104,156 |
Consumer Loans | Total Past Due Loans | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 16,816 | 15,359 |
Consumer Loans | Total Past Due Loans | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,416 | 601 |
Consumer Loans | 30-59 Days Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 5,681 | 2,464 |
Consumer Loans | 30-59 Days Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 912 | 216 |
Consumer Loans | 60-89 Days Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 841 | 2,577 |
Consumer Loans | 60-89 Days Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | $ 286 | $ 155 |

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