Arbitrage Trading Account (Details) - USD ($)	Sep. 30, 2024	Dec. 31, 2023
Derivative [Line Items]
Arbitrage trading account	$ 821,000,000	$ 938,000,000
Long \| Options held
Derivative [Line Items]
Fair value of derivative	6,000,000
Notional amount of derivative	340,000,000
Short \| Options held
Derivative [Line Items]
Fair value of derivative	36,000,000
Notional amount of derivative	$ 340,000,000

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

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Nominal or face amount used to calculate payment on derivative.

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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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