MRBs (Reconciles of MRBs Assets and Liabilities) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Market Risk Benefit [Line Items]
Market risk benefit assets	$ 3,445	$ 2,807
Market risk benefit liabilities	1,976	2,078
Net (Asset) Liability	(1,469)	(729)
Fixed Annuities [Member]
Market Risk Benefit [Line Items]
Market risk benefit assets	114	117
Market risk benefit liabilities	83	72
Net (Asset) Liability	(31)	(45)	$ 114
Retirement Plan Services Segment [Member]
Market Risk Benefit [Line Items]
Market risk benefit assets	26	24
Market risk benefit liabilities		2
Net (Asset) Liability	(26)	(22)	(1)
Variable Annuities [Member]
Market Risk Benefit [Line Items]
Market risk benefit assets	3,305	2,666
Market risk benefit liabilities	1,893	2,004
Net (Asset) Liability	$ (1,412)	$ (662)	$ 2,398