Supplemental Cash Flow Information - Activities resulting from management of proceeds (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Net change in proceeds managed
Net change in fixed income securities	$ 202	$ (373)
Net change in short-term investments	18	(203)
Operating cash flow provided (used)	220	(576)
Net change in cash	0	(12)
Net change in proceeds managed	220	(588)
Change in Liabilities for Collateral [Roll Forward]
Liabilities for collateral, beginning of period	(2,011)	(1,444)
Liabilities for collateral, end of period	(1,791)	(2,032)
Operating cash flow (used) provided	$ (220)	$ 588