Reserves for Future Policy Benefits and Claims Payable - Revenue and Interest Related to Non-Participating Contracts (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	$ 267	$ 400
Interest Expense	303	420
Payout Annuities
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	16	10
Interest Expense	32	40
Closed Block Life
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	250	390
Interest Expense	124	170
Closed Block Annuity
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	1	0
Interest Expense	$ 147	$ 210