Insurance and Contractholder Liabilities - Future Policy Benefits - Interest Rates and Duration (Details) - Other Operations - Life and annuity insurance products	Mar. 31, 2025	Mar. 31, 2024
Insurance and Contractholder Liabilities [Line Items]
Interest accretion rate	5.64%	5.64%
Current discount rate	5.30%	5.16%
Weighted average duration	10 years 9 months 18 days	11 years 3 months 18 days

No definition available.

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- Definition

Current weighted-average discount rate used to measure 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)(6)
-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

Weighted-average duration of liability for future policy benefit, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)(5)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480081/944-40-50-6

+ Details

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- Definition

Original weighted-average discount rate at contract issue date used to measure liability for future policy benefit.

+ References

+ Details

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- Details

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