Supplemental Cash Flow Information - Schedule of Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Net change in proceeds managed
Net change in fixed income securities	$ (4)	$ 259	$ (521)
Net change in short-term investments	(146)	(139)	(49)
Operating cash flow (used) provided	(150)	120	(570)
Net change in cash	0	0	3
Net change in proceeds managed	(150)	120	(567)
Net change in liabilities
Liabilities for collateral, beginning of year	(1,891)	(2,011)	(1,444)
Liabilities for collateral, end of year	(2,041)	(1,891)	(2,011)
Operating cash flow provided (used)	$ 150	$ (120)	$ 567