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Borrowings - Amounts and Interest Rates of Short-term Borrowings (Detail) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Schedule Of Borrowings [Line Items] |  |
Total | $ 1,060 | $ 5,316
Weighted-average interest rate | 4.39% | 5.23%
Repurchase Agreements |  |
Schedule Of Borrowings [Line Items] |  |
Repurchase Agreements | $ 60 | $ 316
Weighted-average interest rate | 2.65% | 3.26%
FHLB Advances |  |
Schedule Of Borrowings [Line Items] |  |
FHLB Advances | $ 1,000 | $ 5,000
Weighted-average interest rate | 4.50% | 5.35%

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