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v3.25.2

Fair Value of Financial Instruments - Changes in the Level 3 Fair Value Category of Unobservable Inputs (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
State and Local Governments Tax-Exempt [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |
Beginning Balance | $ 184 | $ 521 | $ 353 | $ 1,188
Change in Fair Value |  | (1) | 1 | (3)
Payments, Maturities & Calls |  |  | (170) | (665)
Ending Balance | 184 | 520 | 184 | 520
State and Local Governments Taxable[Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |
Beginning Balance | 1,276 | 1,274 | 1,274 | 1,272
Change in Fair Value | (6) | (8) | (4) | (6)
Ending Balance | 1,270 | 1,266 | 1,270 | 1,266
State and Local Governments [Member] |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |
Beginning Balance | 1,460 | 1,795 | 1,627 | 2,460
Change in Fair Value | (6) | (9) | (3) | (9)
Payments, Maturities & Calls |  |  | (170) | (665)
Ending Balance | $ 1,454 | $ 1,786 | $ 1,454 | $ 1,786

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