Future Contract Benefit (Summary of Discounted and Undiscounted Expected Future Gross premiums and Expected Future Benefit Payments) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Traditional Life [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Expected future benefit payments, undiscounted	$ 13,758	$ 13,640
Expected future gross premiums, undiscounted	14,005	13,945
Expected future gross premiums, discounted	9,750	9,475
Expected future benefit payments, Discounted	9,890	9,572
Payout Annuities [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Expected future benefit payments, undiscounted	3,461	3,472
Expected future benefit payments, Discounted	2,068	2,004
Group Protection [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Expected future benefit payments, undiscounted	7,086	7,063
Expected future benefit payments, Discounted	$ 6,061	$ 6,059