Investments - Allowance for credit losses on fixed maturities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Allowance for Credit Losses [Roll Forward]
Beginning balance	$ 11	$ 9
Provision for expected credit losses on securities with no previous allowance	6	0
Additions (reductions) to previously recognized expected credit losses	(1)	(2)
Reductions due to sales or redemptions	0	0
Ending balance	16	7
Structured securities
Allowance for Credit Losses [Roll Forward]
Beginning balance	10	8
Provision for expected credit losses on securities with no previous allowance	1	0
Additions (reductions) to previously recognized expected credit losses	0	(2)
Reductions due to sales or redemptions	0	0
Ending balance	11	6
Corporate and other
Allowance for Credit Losses [Roll Forward]
Beginning balance	1	1
Provision for expected credit losses on securities with no previous allowance	5	0
Additions (reductions) to previously recognized expected credit losses	(1)	0
Reductions due to sales or redemptions	0	0
Ending balance	$ 5	$ 1