Investments - Credit Loss Expense Incurred (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Total intent to sell impairments	$ 0	$ (467)	$ 0	$ (1,091)
Total credit loss benefit (expense)	(7)	(1)	(23)	(21)
Realized Gain (Loss)
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Total credit loss benefit (expense)	(14)	(1)	(40)	(17)
Corporate bonds
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Total intent to sell impairments	0	(422)	0	(941)
Total credit loss benefit (expense)	(6)	(1)	(8)	(21)
Corporate bonds | Realized Gain (Loss)
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Total credit loss benefit (expense)	(9)	(1)	(20)	(18)
State and municipal bonds
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Total intent to sell impairments	0	(28)	0	(48)
RMBS
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Total intent to sell impairments	0	(9)	0	(28)
Total credit loss benefit (expense)	0	0	0	0
RMBS | Realized Gain (Loss)
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Total credit loss benefit (expense)	(1)	0	(1)	1
CMBS
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Total intent to sell impairments	0	(5)	0	(36)
ABS
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Total intent to sell impairments	0	(2)	0	(37)
Total credit loss benefit (expense)	(1)	0	(15)	0
ABS | Realized Gain (Loss)
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Total credit loss benefit (expense)	(4)	0	(19)	0
Hybrid and redeemable preferred securities
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Total intent to sell impairments	$ 0	$ (1)	$ 0	$ (1)