Derivative Instruments - Summary of net realized gains (losses) recorded in the consolidated statements of income (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Net realized gains (losses) on derivative instruments
Net realized gains (losses) on derivative instruments	[1]	$ 30	$ 125	$ 292	$ 116
Not designated as hedging instrument
Net realized gains (losses) on derivative instruments
Net realized gains (losses) on derivative instruments		30	125	292	116
Not designated as hedging instrument | Futures contracts
Net realized gains (losses) on derivative instruments
Net realized gains (losses) on derivative instruments		37	86	176	69
Not designated as hedging instrument | Foreign currency forward contracts
Net realized gains (losses) on derivative instruments
Net realized gains (losses) on derivative instruments		(12)	31	71	32
Not designated as hedging instrument | Other
Net realized gains (losses) on derivative instruments
Net realized gains (losses) on derivative instruments	[2]	$ 5	$ 8	$ 45	$ 15

[1] See note 10 for information on the Company’s derivative instruments.

[2] Includes realized gains or losses on swaps, options and other derivatives contracts