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v3.25.1

INVESTMENTS (Narrative) (Detail) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2024 | Dec. 31, 2023
Schedule of Investments [Line Items] |  |  |  |  |
Trading securities | $ 4,860,000 |  |  | $ 5,243,000 |
AFS debt securities, allowance | 0 |  |  | 0 |
Net unrealized loss on debt securities, net of tax | 49,000,000.0 |  |  | 62,200,000 |
Deferred tax assets, unrealized losses on available for sale securities | 14,100,000 |  |  | 17,000,000 |
Provision for credit losses, HTM debt securities | 0 | $ (910,000) | $ 1,800,000 | 0 |
Write off, accrued interest, HTM debt securities |  | 910,000 |  |  |
HTM debt securities, excluding accrued interest from amortized cost | 1,400,000 |  |  | 1,600,000 |
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Recovery | 0 | $ 910,000 |  |  |
Asset Pledged as Collateral |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
AFS and HTM debt securities, amortized cost | 743,500,000 |  |  | 519,900,000 |
AFS and HTM debt securities, fair value | 680,500,000 |  |  | 449,000,000.0 |
Available-for-sale Securities |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Interest receivable | 2,300,000 |  |  | 1,700,000 |
Transferred Securities |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
AFS debt securities transferred to HTM, fair value |  |  |  |  | $ 520,300,000
AFS debt securities, transfer, unrealized loss |  |  |  |  | $ 72,100,000
Net unrealized loss on debt securities, net of tax | (40,700,000) |  |  | (41,800,000) |
Deferred tax assets, unrealized losses on available for sale securities | $ 11,800,000 |  |  | $ 11,400,000 |

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