Investments - OTTI losses by asset type (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Realized capital gains and losses by asset type
Fixed income securities	$ (12)	$ 7	$ 2	$ (29)
Total credit losses by asset type	(12)	6	2	(30)
Commitments to fund commercial mortgage loans, bank loans and agent loans	0	1	0	1
Fixed income securities
Realized capital gains and losses by asset type
Fixed income securities	0	(1)	1	(4)
Corporate
Realized capital gains and losses by asset type
Fixed income securities	0	(1)	0	(2)
ABS
Realized capital gains and losses by asset type
Fixed income securities	0	0	1	(2)
Mortgage loans
Realized capital gains and losses by asset type
Total credit losses by asset type	0	1	17	(2)
Limited partnership interests
Realized capital gains and losses by asset type
Total credit losses by asset type	0	0	0	(6)
Bank loans, net
Realized capital gains and losses by asset type
Total credit losses by asset type	(13)	6	(16)	(18)
Agent loans, net
Realized capital gains and losses by asset type
Total credit losses by asset type	$ 1	$ 0	$ 0	$ 0