Other Policyholder Funds and Benefits Payable (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Other policyholder funds and benefits payable	$ 633	$ 647	$ 638
Universal Life
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Other policyholder funds and benefits payable	218	231	$ 223	$ 232
Policyholder Account Balance, Premium Received	3	3
Policyholder Account Balance, Policy Charge	5	5
Policyholder Account Balance, Surrender and Withdrawal	1	1
Policyholder Account Balance, Benefit Payment	4	1
Policyholder Account Balance, Interest Expense	$ 2	$ 3
Policyholder Account Balance, Weighted Average Crediting Rate	4.20%	4.20%
Policyholder Account Balance, Net Amount at Risk	$ 897	$ 966
Policyholder Account Balance, Cash Surrender Value	$ 216	229
Universal Life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 to 0499 | Minimum
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Policyholder Account Balance, Guaranteed Minimum Credit Rating	4.00%
Universal Life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 to 0499 | Maximum
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Policyholder Account Balance, Guaranteed Minimum Credit Rating	5.00%
Universal Life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 to 0499 | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Other policyholder funds and benefits payable	$ 217	229
Short-Duration Insurance, Other
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Other policyholder funds and benefits payable	$ 415	$ 416