Supplemental Cash Flow Information - Activities resulting from management of proceeds (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Net change in proceeds managed
Net change in fixed income securities	$ 111	$ 0
Net change in short-term investments	93	(63)
Operating cash flow provided (used)	204	(63)
Net change in cash	0	3
Net change in proceeds managed	204	(60)
Change in Liabilities for Collateral [Roll Forward]
Liabilities for collateral, beginning of period	(2,011)	(1,444)
Liabilities for collateral, end of period	(1,807)	(1,504)
Operating cash flow (used) provided	$ (204)	$ 60