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

+ Details

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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 ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2024
Income Taxes [Line Items]
Net discrete tax expense	$ 7	$ 8	$ 9	$ 15
Uncertain tax positions from expirations of statute of limitations	$ 0	$ 0	$ 2	$ 1
United States Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2021 2022 2023
State Tax Authorities [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2021 2022 2023
Foreign Jurisdictions [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024