Future Policy Benefits - Liability For Future Policy Benefit Expected Future Policy Benefit Undiscounted (Details) - USD ($) $ in Millions	Jun. 30, 2023	Jun. 30, 2022
Liability For Future Policy Benefit, Expected Future Policy Benefit, Discounted [Abstract]
Expected future benefit payments		$ 2,686
Expected future gross premiums		1,091
Traditional Life
Liability for Future Policy Benefit, Expected Future Policy Benefit, Undiscounted [Abstract]
Expected future benefit payments	$ 3,027	3,201
Expected future gross premiums	1,114	1,245
Liability For Future Policy Benefit, Expected Future Policy Benefit, Discounted [Abstract]
Expected future benefit payments	2,089
Expected future gross premiums	803
Immediate Annuities
Liability for Future Policy Benefit, Expected Future Policy Benefit, Undiscounted [Abstract]
Expected future benefit payments	3,361	3,516
Expected future gross premiums	0	0
Liability For Future Policy Benefit, Expected Future Policy Benefit, Discounted [Abstract]
Expected future benefit payments	1,411	1,907
Expected future gross premiums	0	0
PRT
Liability for Future Policy Benefit, Expected Future Policy Benefit, Undiscounted [Abstract]
Expected future benefit payments	4,724	2,265
Expected future gross premiums	0	0
Liability For Future Policy Benefit, Expected Future Policy Benefit, Discounted [Abstract]
Expected future benefit payments	3,161	1,652
Expected future gross premiums	$ 0	$ 0

Liability For Future Policy Benefit, Expected Future Policy Benefit, Discounted

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- Definition

Liability For Future Policy Benefit, Expected Future Policy Benefit, Discounted, Before Reinsurance

+ References

No definition available.

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- Definition

Liability for Future Policy Benefit, Expected Future Policy Benefit, Undiscounted

+ References

No definition available.

+ Details

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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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- Definition

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

+ References

+ Details

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