Arbitrage Trading Account (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Derivative [Line Items]
Arbitrage trading account	$ 1,035	$ 1,123
Long \| Options held
Derivative [Line Items]
Fair value of derivative	5
Notional amount of derivative	270
Short \| Options held
Derivative [Line Items]
Fair value of derivative	31
Notional amount of derivative	$ 271

Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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