Insurance Liabilities - Expected Future Benefits, Expenses, and Gross Premiums (Details) - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023
Insurance [Abstract]
Undiscounted expected future benefits and expense	$ 2,820	$ 3,099
Undiscounted expected future gross premiums	3,881	4,275
Discounted expected future gross premiums (at current discount rate)	$ 2,905	$ 2,963

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.

+ References

+ Details

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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

+ Details

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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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