Future Contract Benefits - Summary of Discounted and Undiscounted Expected Future Gross premiums and Expected Future Benefit Payments (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Payout Annuities
Undiscounted
Expected future gross premiums	$ 0	$ 0
Expected future benefit payments	3,481	3,471
Discounted
Expected future gross premiums	0	0
Expected future benefit payments	2,084	2,003
Traditional Life
Undiscounted
Expected future gross premiums	13,406	13,166
Expected future benefit payments	13,404	13,026
Discounted
Expected future gross premiums	9,341	8,887
Expected future benefit payments	9,637	9,086
Group Protection
Undiscounted
Expected future benefit payments	7,250	7,063
Discounted
Expected future benefit payments	$ 6,179	$ 6,059

Liability For Future Policy Benefit, Discounted, Befiore Reinsurance

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Liability for future policy benefit, expected future policy benefit, discounted, before reinsurance.

+ References

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- Definition

Liability For Future Policy Benefit, Undiscounted, Befiore Reinsurance

+ References

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- Definition

Amount, before effect of reinsurance, of discounted balance for expected future gross premium component of liability for future policy benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480081/944-40-50-6

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- Definition

Amount, before effect of reinsurance, of undiscounted balance for expected future gross premium component of liability for future policy benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 29E
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480046/944-40-55-29E

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480081/944-40-50-6

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Amount, before effect of reinsurance, of undiscounted balance for expected future policy benefit and expense component of liability for future policy benefit.

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