Fair Value Measurements - Schedule of Quantitative Information on Significant Internally-Priced Level 3 Assets and Liabilities (Details) $ in Millions	Mar. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits	$ 18,926	$ 19,518
Market risk benefit assets	6,701	7,867
Market risk benefit liabilities	3,971	3,754
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits	121	118
Market risk benefit assets	6,701	7,867
Market risk benefit liabilities	3,971	3,754
Level 3 \| Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits	121	118
Market risk benefit assets	6,701	7,867
Market risk benefit liabilities	$ 3,971	$ 3,754
Level 3 \| Discounted cash flow \| Minimum \| Mortality
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits, measurement input	0.0001	0.0001
Market risk benefit, assets, measurement input	0.0000	0.0000
Market risk benefit, liabilities, measurement input	0.0000	0.0000
Level 3 \| Discounted cash flow \| Minimum \| Lapse
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits, measurement input	0.0151	0.0151
Market risk benefit, assets, measurement input	0.0005	0.0005
Market risk benefit, liabilities, measurement input	0.0005	0.0005
Level 3 \| Discounted cash flow \| Minimum \| Utilization
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits, measurement input	0.0000	0.0000
Market risk benefit, assets, measurement input	0.0000	0.0000
Market risk benefit, liabilities, measurement input	0.0000	0.0000
Level 3 \| Discounted cash flow \| Minimum \| Withdrawal
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits, measurement input	0.4100	0.4100
Market risk benefit, assets, measurement input	0.0415	0.0415
Market risk benefit, liabilities, measurement input	0.0415	0.0415
Level 3 \| Discounted cash flow \| Minimum \| Non-performance risk adjustment
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits, measurement input	0.0038	0.0030
Market risk benefit, assets, measurement input	0.0092	0.0057
Market risk benefit, liabilities, measurement input	0.0092	0.0057
Level 3 \| Discounted cash flow \| Minimum \| Long-term Equity Volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits, measurement input	0.1750	0.1750
Market risk benefit, assets, measurement input	0.1750	0.1750
Market risk benefit, liabilities, measurement input	0.1750	0.1750
Level 3 \| Discounted cash flow \| Maximum \| Mortality
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits, measurement input	0.2331	0.2331
Market risk benefit, assets, measurement input	0.2814	0.2814
Market risk benefit, liabilities, measurement input	0.2814	0.2814
Level 3 \| Discounted cash flow \| Maximum \| Lapse
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits, measurement input	0.1343	0.1343
Market risk benefit, assets, measurement input	0.5100	0.5100
Market risk benefit, liabilities, measurement input	0.5100	0.5100
Level 3 \| Discounted cash flow \| Maximum \| Utilization
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits, measurement input	0.5000	0.5000
Market risk benefit, assets, measurement input	1.0000	1.0000
Market risk benefit, liabilities, measurement input	1.0000	1.0000
Level 3 \| Discounted cash flow \| Maximum \| Withdrawal
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits, measurement input	0.4850	0.4850
Market risk benefit, assets, measurement input	1.0000	1.0000
Market risk benefit, liabilities, measurement input	1.0000	1.0000
Level 3 \| Discounted cash flow \| Maximum \| Non-performance risk adjustment
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits, measurement input	0.0122	0.0109
Market risk benefit, assets, measurement input	0.0198	0.0167
Market risk benefit, liabilities, measurement input	0.0198	0.0167
Level 3 \| Discounted cash flow \| Maximum \| Long-term Equity Volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Reinsurance recoverable on market risk benefits, measurement input	0.2350	0.2350
Market risk benefit, assets, measurement input	0.2350	0.2350
Market risk benefit, liabilities, measurement input	0.2350	0.2350