MRBs - Reconciles of MRBs Assets and Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Dec. 31, 2023
Market Risk Benefit [Line Items]
Assets	$ 4,694	$ 4,860
Liabilities	1,190	1,046
Net (Assets) Liabilities	(3,504)	(3,814)
Variable Annuities
Market Risk Benefit [Line Items]
Assets	4,595	4,737
Liabilities	1,013	933
Net (Assets) Liabilities	(3,582)	(3,804)	$ (3,327)	$ (2,180)
Fixed Annuities
Market Risk Benefit [Line Items]
Assets	53	78
Liabilities	174	110
Net (Assets) Liabilities	121	32	74	32
Retirement Plan Services
Market Risk Benefit [Line Items]
Assets	46	45
Liabilities	3	3
Net (Assets) Liabilities	$ (43)	$ (42)	$ (40)	$ (30)