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Loans and Allowance for Credit Losses - Summary of Aging Analysis of Modifications (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Mar. 31, 2024
--- | --- | ---
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | $ 23,328 | $ 18,797
Current | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 18,280 | 8,694
30-59 Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 1,230 | 2,105
60-89 Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 40 | 7,998
90+ Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 3,778 | 0
Commercial Loans | Commercial real estate |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 616 | 8,579
Commercial Loans | Commercial real estate | Current | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 616 | 8,579
Commercial Loans | Commercial real estate | 30-59 Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 0 | 0
Commercial Loans | Commercial real estate | 60-89 Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 0 | 0
Commercial Loans | Commercial real estate | 90+ Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 0 | 0
Commercial Loans | Commercial and industrial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 20,314 | 10,103
Commercial Loans | Commercial and industrial | Current | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 16,536 | 0
Commercial Loans | Commercial and industrial | 30-59 Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 0 | 2,105
Commercial Loans | Commercial and industrial | 60-89 Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 0 | 7,998
Commercial Loans | Commercial and industrial | 90+ Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 3,778 | 0
Commercial Loans | Commercial construction |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 1,006 |
Commercial Loans | Commercial construction | Current | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 0 |
Commercial Loans | Commercial construction | 30-59 Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 1,006 |
Commercial Loans | Commercial construction | 60-89 Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 0 |
Commercial Loans | Commercial construction | 90+ Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 0 |
Business banking |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months |  | 115
Business banking | Current | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months |  | 115
Business banking | 30-59 Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months |  | 0
Business banking | 60-89 Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months |  | 0
Business banking | 90+ Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months |  | $ 0
Consumer Loans | Consumer real estate |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 1,392 |
Consumer Loans | Consumer real estate | Current | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 1,128 |
Consumer Loans | Consumer real estate | 30-59 Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 224 |
Consumer Loans | Consumer real estate | 60-89 Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | 40 |
Consumer Loans | Consumer real estate | 90+ Days Past Due | Accrual |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modified, after 12 months | $ 0 |

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