Investments (Allowance on available-for-sale securities with credit impairments and PCD assets activity) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Allowance for credit losses:
Balance, beginning of period	$ 2	$ 17	$ 1	$ 18
Additions to the allowance for credit losses:
Securities for which credit losses were not previously recorded	8	0	8	0
Available-for-sale securities accounted for as PCD assets	11	3	20	3
Reductions to the allowance for credit losses:
Securities sold during the period (realized)			6	0
Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis			3	0
Write-offs charged against the allowance	0	12	0	12
Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period	1	(3)	2	(4)
Balance, end of period	22	5	22	5
Corporate and other bonds
Allowance for credit losses:
Balance, beginning of period	1	12	0	11
Additions to the allowance for credit losses:
Securities for which credit losses were not previously recorded	1	0	1	0
Available-for-sale securities accounted for as PCD assets	11	0	20	0
Reductions to the allowance for credit losses:
Securities sold during the period (realized)			6	0
Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis			3	0
Write-offs charged against the allowance	0	12	0	12
Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period	0	0	1	1
Balance, end of period	13	0	13	0
Asset-backed
Allowance for credit losses:
Balance, beginning of period	1	5	1	7
Additions to the allowance for credit losses:
Securities for which credit losses were not previously recorded	7	0	7	0
Available-for-sale securities accounted for as PCD assets	0	3	0	3
Reductions to the allowance for credit losses:
Securities sold during the period (realized)			0	0
Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis			0	0
Write-offs charged against the allowance	0	0	0	0
Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period	1	(3)	1	(5)
Balance, end of period	$ 9	$ 5	$ 9	$ 5