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Arbitrage Trading Account (Details) - USD ($)	Dec. 31, 2024	Dec. 31, 2023
Trading Securities and Derivative Instruments [Abstract]
Arbitrage trading account	$ 1,123,000,000	$ 938,000,000
Options Held | Short
Derivative [Line Items]
Other derivatives not designated as hedging instruments at fair value, net	73,000,000
Derivative, notional amount	582,000,000
Options Held | Long
Derivative [Line Items]
Other derivatives not designated as hedging instruments at fair value, net	26,000,000
Derivative, notional amount	$ 582,000,000

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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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