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Derivative and Hedging Activities and Restricted Cash - Company's Carrying Amounts on our Hedged Loans (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024
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Loans and Leases Held-For-Investment |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Carrying Amount of Hedged Items | $ 4,245 | $ 5,861
Cumulative Amount of Fair Value Hedging Adjustment | (12) | (18)
Available-for-Sale Securities |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Carrying Amount of Hedged Items | 993 | 0
Cumulative Amount of Fair Value Hedging Adjustment | $ 7 | $ 0

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