Investments - Allowance for credit losses on fixed maturities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Allowance for Credit Losses [Roll Forward]
Beginning balance	$ 12	$ 11
Provision for expected credit losses on securities with no previous allowance	1	6
Additions (reductions) to previously recognized expected credit losses	1	(1)
Reductions due to sales or redemptions	(3)	0
Ending balance	11	16
Structured securities
Allowance for Credit Losses [Roll Forward]
Beginning balance	9	10
Provision for expected credit losses on securities with no previous allowance	1	1
Additions (reductions) to previously recognized expected credit losses	1	0
Reductions due to sales or redemptions	0	0
Ending balance	11	11
Corporate and other
Allowance for Credit Losses [Roll Forward]
Beginning balance	3	1
Provision for expected credit losses on securities with no previous allowance	0	5
Additions (reductions) to previously recognized expected credit losses	0	(1)
Reductions due to sales or redemptions	(3)	0
Ending balance	$ 0	$ 5