Fair Value - Summary of Unobservable Inputs for the Embedded Derivatives of Interest Sensitive Contract Liabilities (Details) $ in Millions	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	$ 128,559	$ 112,225
Investment funds	15,868	14,128
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	13,800	10,671
Mortgage loans, net of allowances	38,077	30,811
Level 3 \| Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment funds	502	506
Level 3 \| Discounted cash flow/guideline public equity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment funds		873
Level 3 \| Net tangible asset values
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment funds	512	529
Level 3 \| Reported net asset value
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment funds	$ 337	$ 563
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	0.018	0.017
Nonperformance risk \| Weighted average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.012	0.010
Option budget \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.005	0.005
Option budget \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.057	0.053
Option budget \| Weighted average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.022	0.019
Surrender rate \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.054	0.051
Surrender rate \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.120	0.115
Surrender rate \| Weighted average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.081	0.081
Measurement Input, Discount Rate [Member] \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0.022	0.022
Mortgage loans, Measurement Input	0.020	0.015
Investment funds, measurement input	0.064	0.064
Measurement Input, Discount Rate [Member] \| Minimum \| Discounted cash flow/guideline public equity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment funds, measurement input		0.165
Measurement Input, Discount Rate [Member] \| Minimum \| Measurement Input, Implied Multiple
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment funds, measurement input	1.20	1.26
Measurement Input, Discount Rate [Member] \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0.187	0.188
Mortgage loans, Measurement Input	0.242	0.221
Investment funds, measurement input	0.064	0.064
Measurement Input, Discount Rate [Member] \| Maximum \| Discounted cash flow/guideline public equity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment funds, measurement input		0.165
Measurement Input, Discount Rate [Member] \| Maximum \| Measurement Input, Implied Multiple
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment funds, measurement input	1.20	1.26
Measurement Input, Discount Rate [Member] \| Weighted average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0.069	0.068
Mortgage loans, Measurement Input	0.065	0.063
Investment funds, measurement input	0.064	0.064
Measurement Input, Discount Rate [Member] \| Weighted average \| Discounted cash flow/guideline public equity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment funds, measurement input		0.165
Measurement Input, Discount Rate [Member] \| Weighted average \| Measurement Input, Implied Multiple
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment funds, measurement input	1.20	1.26
Measurement Input, P/E Ratio \| Minimum \| Discounted cash flow/guideline public equity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment funds, measurement input		9
Measurement Input, P/E Ratio \| Maximum \| Discounted cash flow/guideline public equity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment funds, measurement input		9
Measurement Input, P/E Ratio \| Weighted average \| Discounted cash flow/guideline public equity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment funds, measurement input		9
Embedded derivatives \| Interest sensitive contract liabilities \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total liabilities measured at fair value	$ 8,198	$ 5,841

Other investments including, but not limited to: partnership interests, credit funds, hedge funds, and private equity.

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Mortgage loans, Measurement Input

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Fair value of financial and nonfinancial obligations.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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