Fair Value - Significant Unobservable Inputs (Details) $ in Millions	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Quantitative Information About the Significant Unobservable Inputs [Abstract]
Estimated Fair Value	$ 39,431	$ 44,380
Level 3 \| Fixed maturity securities
Quantitative Information About the Significant Unobservable Inputs [Abstract]
Estimated Fair Value	$ 1,117	$ 1,225
Debt Securities, Available-for-sale, Valuation Technique [Extensible List]	Range (Weighted Average)	Range (Weighted Average)
Debt Securities, Available-for-sale, Measurement Input [Extensible List]	Credit spread	Credit spread
Credit spread \| Minimum \| Level 3 \| Fixed maturity securities \| Range (Weighted Average)
Quantitative Information About the Significant Unobservable Inputs [Abstract]
Measurement input	0.01	0.01
Credit spread \| Maximum \| Level 3 \| Fixed maturity securities \| Range (Weighted Average)
Quantitative Information About the Significant Unobservable Inputs [Abstract]
Measurement input	0.09	0.07
Credit spread \| Weighted Average \| Level 3 \| Fixed maturity securities \| Range (Weighted Average)
Quantitative Information About the Significant Unobservable Inputs [Abstract]
Measurement input	0.03	0.02

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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