Future Policy Benefits - Schedule of Liability For Future Policy Benefit Expected Future Policy Benefit Undiscounted (Details) - USD ($) $ in Millions	Mar. 31, 2025	Mar. 31, 2024
Traditional Life
Undiscounted
Expected future benefit payments	$ 2,720	$ 2,874
Expected future gross premiums	923	1,042
Discounted
Expected future benefit payments	1,938	2,013
Expected future gross premiums	671	751
Immediate annuities
Undiscounted
Expected future benefit payments	3,168	3,271
Expected future gross premiums	0	0
Discounted
Expected future benefit payments	1,297	1,371
Expected future gross premiums	0	0
PRT
Undiscounted
Expected future benefit payments	10,535	8,344
Expected future gross premiums	0	0
Discounted
Expected future benefit payments	6,360	4,899
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.

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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.

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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/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

Reference 2: 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

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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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