Fair Value - Significant Unobservable Inputs (Details) $ in Millions	Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Quantitative Information About the Significant Unobservable Inputs [Abstract]
Estimated Fair Value	$ 37,504	$ 44,380
Level 3 \| Fixed maturity securities
Quantitative Information About the Significant Unobservable Inputs [Abstract]
Estimated Fair Value	$ 1,111	$ 1,225
Debt Securities, Available-for-sale, Valuation Technique [Extensible List]	Discounted cash flow	Discounted cash flow
Debt Securities, Available-for-sale, Measurement Input [Extensible List]	Credit spread	Credit spread
Credit spread \| Minimum \| Level 3 \| Fixed maturity securities \| Discounted cash flow
Quantitative Information About the Significant Unobservable Inputs [Abstract]
Measurement input	0.01	0.01
Credit spread \| Maximum \| Level 3 \| Fixed maturity securities \| Discounted cash flow
Quantitative Information About the Significant Unobservable Inputs [Abstract]
Measurement input	0.11	0.07
Credit spread \| Weighted Average \| Level 3 \| Fixed maturity securities \| Discounted cash flow
Quantitative Information About the Significant Unobservable Inputs [Abstract]
Measurement input	0.03	0.02

Amount excluding accrued interest, 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/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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- Definition

Indicates valuation technique for measuring investment in debt security at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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