Separate Account (Schedule of Fair Value of Separate Account Assets) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Separate Account, Liability [Line Items]
Separate account liabilities	$ 148,421	$ 143,536
UL and Other [Member]
Separate Account, Liability [Line Items]
Separate account liabilities	22,162	20,920	$ 24,785
Retirement Plan Services Segment [Member]
Separate Account, Liability [Line Items]
Separate account liabilities	17,876	16,996	21,068
Other Operations [Member]
Separate Account, Liability [Line Items]
Separate account liabilities	49	47
Variable Annuities [Member]
Separate Account, Liability [Line Items]
Separate account liabilities	108,334	105,573	$ 136,665
Reinsurance Agreement [Member]
Separate Account, Liability [Line Items]
Separate account liabilities	$ 43	$ 42