Income taxes.

No definition available.

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- Definition

Net discrete tax benefits charges related to tax settlements.

+ References

No definition available.

+ Details

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- Definition

Tax year that remains open to examination under enacted tax laws, in YYYY format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-15

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- Definition

Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15A
-Subparagraph (a)(4)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-15A

+ Details

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Income Tax - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
Income Tax - Additional Information (Detail) - USD ($)	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023
Income Taxes [Line Items]
Net discrete tax (benefits) expense related to tax settlements	$ 8,000,000	$ (2,000,000)	$ 15,000,000	$ 1,000,000
Uncertain tax positions from expirations of statute of limitations	$ 0		$ 1,000,000	$ 1,000,000
Maximum [Member]
Income Taxes [Line Items]
Uncertain tax positions from expirations of statute of limitations		$ 1,000,000
United States Internal Revenue Service (IRS) [Member] \| Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2020
United States Internal Revenue Service (IRS) [Member] \| Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2022
State Tax Authorities [Member] \| Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2018
State Tax Authorities [Member] \| Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2022
Foreign Jurisdictions [Member] \| Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2006
Foreign Jurisdictions [Member] \| Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2023