Significant Accounting Policies (Details)	12 Months Ended
Sep. 30, 2025
Accounting Policies [Abstract]
Market-related valuation calculation period (in years)	5 years
Net unrecognized gain (loss) threshold subject to amortization (in percent)	10.00%
Minimum \| Building
Property and equipment
Estimated useful live (in years)	10 years
Minimum \| Furniture and fixtures
Property and equipment
Estimated useful live (in years)	3 years
Minimum \| Computer systems and equipment
Property and equipment
Estimated useful live (in years)	3 years
Maximum \| Building
Property and equipment
Estimated useful live (in years)	45 years
Maximum \| Furniture and fixtures
Property and equipment
Estimated useful live (in years)	10 years
Maximum \| Computer systems and equipment
Property and equipment
Estimated useful live (in years)	12 years

Represents the percentage of the greater of the projected benefit obligation or the market related value of plan assets that has to be exceeded for amortization of cumulative net unrecognized gains or losses.

No definition available.

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- Definition

Represents the amortization period of the difference between the actual return (including capital, dividends, and interest) and the expected return in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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