Fair Value - Summary of Unobservable Inputs for the Embedded Derivatives of Interest Sensitive Contract Liabilities (Details) $ in Millions	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	$ 100,966	$ 110,561
Mortgage loans, net of allowances		24,148
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	10,186	$ 10,167
Mortgage loans, net of allowances	$ 28,259
Nonperformance risk | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.004	0.001
Nonperformance risk | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.020	0.010
Nonperformance risk | Weighted Average [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.013	0.006
Option budget | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.005	0.004
Option budget | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.041	0.034
Option budget | Weighted Average [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.017	0.019
Surrender rate | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.050	0.059
Surrender rate | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.109	0.107
Surrender rate | Weighted Average [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.079	0.080
Measurement Input, Discount Rate [Member] | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0.016	0.014
Mortgage loans, Measurement Input	0.025
Measurement Input, Discount Rate [Member] | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0.220	0.194
Mortgage loans, Measurement Input	0.239
Measurement Input, Discount Rate [Member] | Weighted Average [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0.053	0.052
Mortgage loans, Measurement Input	0.052
Embedded derivatives | Interest sensitive contract liabilities | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total liabilities measured at fair value	$ 5,451	$ 14,907