Long-duration Contracts - Schedule of Unobservable Inputs for Market Risk Benefits (Details) $ in Millions	Mar. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Market Risk Benefit [Line Items]
Market risk benefits, net	$ 4,827	$ 4,716	$ 4,077	$ 3,715
Minimum \| Nonperformance risk \| Discounted cash flow
Market Risk Benefit [Line Items]
Market risk benefits, measurement input (as percent)	0.005		0.005
Minimum \| Option budget \| Discounted cash flow
Market Risk Benefit [Line Items]
Market risk benefits, measurement input (as percent)	0.005		0.005
Minimum \| Surrender rate \| Discounted cash flow
Market Risk Benefit [Line Items]
Market risk benefits, measurement input (as percent)	0.039		0.031
Minimum \| Utilization rate \| Discounted cash flow
Market Risk Benefit [Line Items]
Market risk benefits, measurement input (as percent)	0.286		0.286
Maximum \| Nonperformance risk \| Discounted cash flow
Market Risk Benefit [Line Items]
Market risk benefits, measurement input (as percent)	0.013		0.013
Maximum \| Option budget \| Discounted cash flow
Market Risk Benefit [Line Items]
Market risk benefits, measurement input (as percent)	0.059		0.060
Maximum \| Surrender rate \| Discounted cash flow
Market Risk Benefit [Line Items]
Market risk benefits, measurement input (as percent)	0.079		0.068
Maximum \| Utilization rate \| Discounted cash flow
Market Risk Benefit [Line Items]
Market risk benefits, measurement input (as percent)	0.950		0.950
Weighted Average \| Nonperformance risk \| Discounted cash flow
Market Risk Benefit [Line Items]
Market risk benefits, measurement input (as percent)	0.011		0.011
Weighted Average \| Option budget \| Discounted cash flow
Market Risk Benefit [Line Items]
Market risk benefits, measurement input (as percent)	0.027		0.024
Weighted Average \| Surrender rate \| Discounted cash flow
Market Risk Benefit [Line Items]
Market risk benefits, measurement input (as percent)	0.052		0.045
Weighted Average \| Utilization rate \| Discounted cash flow
Market Risk Benefit [Line Items]
Market risk benefits, measurement input (as percent)	0.865		0.851