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Loans and Leases and the Allowance for Credit Losses - Summary of Payment Status of Loans Modified (Detail) - USD ($) $ in Thousands | Mar. 31, 2025 | Mar. 31, 2024
--- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | $ 1,292,000 | $ 1,878,000
Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,108,000 | 1,693,000
30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 117,000 | 121,000
Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 67,000 | 64,000
Commercial and industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 313,000 | 327,000
Commercial and industrial | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 293,000 | 310,000
Commercial and industrial | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 3,000 | 7,000
Commercial and industrial | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 17,000 | 10,000
Commercial Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 468,000 | 772,000
Commercial Real Estate | Commercial | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 419,000 | 715,000
Commercial Real Estate | Commercial | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 49,000 | 33,000
Commercial Real Estate | Commercial | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 24,000
Commercial Real Estate | Residential builder and developer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,000 | 53,000
Commercial Real Estate | Residential builder and developer | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,000 | 14,000
Commercial Real Estate | Residential builder and developer | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 39,000
Commercial Real Estate | Residential builder and developer | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Commercial Real Estate | Other commercial construction |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 328,000 | 539,000
Commercial Real Estate | Other commercial construction | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 289,000 | 534,000
Commercial Real Estate | Other commercial construction | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 30,000 | 5,000
Commercial Real Estate | Other commercial construction | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 9,000 | 0
Residential Real Estate | Residential |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 180,000 | 185,000
Residential Real Estate | Residential | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 104,000 | 118,000
Residential Real Estate | Residential | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 35,000 | 37,000
Residential Real Estate | Residential | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 41,000 | 30,000
Consumer: | Home equity lines and loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,000 | 2,000
Consumer: | Home equity lines and loans | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,000 | 2,000
Consumer: | Home equity lines and loans | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer: | Home equity lines and loans | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer: | Recreational finance |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,000 | 0
Consumer: | Recreational finance | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,000 | 0
Consumer: | Recreational finance | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer: | Recreational finance | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer: | Automobile |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer: | Automobile | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer: | Automobile | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer: | Automobile | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer: | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer: | Other | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer: | Other | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer: | Other | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | $ 0 | $ 0

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