Policyholder Account Balances, Future Policy Benefits and Claims - Additional Liabilities (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Additional Liability, Long-Duration Insurance [Roll Forward]
Beginning balance	$ 1,186	$ 1,242
Interest accrual	9	38
Benefit accrual	36	116
Benefit payments	(17)	(61)
Effect of actual variances from expected experience		(6)	$ (19)
Impact of change in net unrealized (gains) losses on securities	16	(130)
Ending balance	1,224	1,186
Universal Life Insurance
Additional Liability, Long-Duration Insurance [Roll Forward]
Beginning balance	1,100	1,120
Interest accrual	8	32
Benefit accrual	33	108
Benefit payments	(12)	(43)
Effect of actual variances from expected experience		(5)	(19)
Impact of change in net unrealized (gains) losses on securities	12	(98)
Ending balance	$ 1,136	$ 1,100
Weighted average interest accretion rate	2.90%	2.90%
Weighted average discount rate	3.20%	3.20%
Weighted average duration of reserves (in years)	10 years	10 years
Variable Universal Life Insurance
Additional Liability, Long-Duration Insurance [Roll Forward]
Beginning balance	$ 74	$ 76
Interest accrual	1	5
Benefit accrual	2	8
Benefit payments	(4)	(14)
Effect of actual variances from expected experience		0	2
Impact of change in net unrealized (gains) losses on securities	1	(3)
Ending balance	$ 74	$ 74
Weighted average interest accretion rate	7.10%	7.00%
Weighted average discount rate	7.10%	7.10%
Weighted average duration of reserves (in years)	8 years	8 years
Other Life Insurance
Additional Liability, Long-Duration Insurance [Roll Forward]
Beginning balance	$ 12	$ 46
Interest accrual	0	1
Benefit accrual	1	0
Benefit payments	(1)	(4)
Effect of actual variances from expected experience		(1)	$ (2)
Impact of change in net unrealized (gains) losses on securities	3	(29)
Ending balance	$ 14	$ 12
Weighted average interest accretion rate	3.90%	4.10%
Weighted average discount rate	4.00%	4.00%
Weighted average duration of reserves (in years)	6 years	6 years