Investments - Rollforward of Changes in Allowance for Credit Losses on Available for Sale Fixed Maturity Securities by Major Investment Category (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	$ 38	$ 34
Securities for which allowance for credit losses was not previously recorded	2	4
Securities sold during the period	(4)	1
Addition to (release of) the allowance for credit losses on securities that had an allowance recorded in a previous period, for which there was no intent to sell before recovery of amortized cost basis	2	(3)
Write-offs charged against the allowance	(8)	(8)
Balance, end of period	30	28
Structured
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	10	13
Securities for which allowance for credit losses was not previously recorded	0	0
Securities sold during the period	0	0
Addition to (release of) the allowance for credit losses on securities that had an allowance recorded in a previous period, for which there was no intent to sell before recovery of amortized cost basis	1	(10)
Write-offs charged against the allowance	0	0
Balance, end of period	11	3
Non- Structured
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	28	21
Securities for which allowance for credit losses was not previously recorded	2	4
Securities sold during the period	(4)	1
Addition to (release of) the allowance for credit losses on securities that had an allowance recorded in a previous period, for which there was no intent to sell before recovery of amortized cost basis	1	7
Write-offs charged against the allowance	(8)	(8)
Balance, end of period	$ 19	$ 25