Arbitrage Trading Account (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Trading Securities and Derivative Instruments [Abstract]
Arbitrage trading account	$ 938,000,000	$ 944,000,000
Options Held | Short
Derivative [Line Items]
Other derivatives not designated as hedging instruments at fair value, net	9,000,000
Derivative, notional amount	75,000,000
Options Held | Long
Derivative [Line Items]
Other derivatives not designated as hedging instruments at fair value, net	185,000
Derivative, notional amount	$ 75,000,000