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Income Tax - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Income Taxes [Line Items] |  |  |  |
Net discrete tax (benefits) expense related to tax settlements |  | $ 14 |  | $ (22)
Tax expense related to withholding tax accruals on historic earnings due to changes in indefinite reinvestment assertion on certain entities | $ 2 |  | $ 3 | 8
Uncertain tax positions from expirations of statute of limitations | $ 0 | $ 0 | $ 1 | 2
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 |  |  | 2013 |
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 |  |  | 2005 |
Foreign Jurisdictions [Member] | Latest Tax Year [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Tax years remain subject to examination |  |  | 2022 |
Purification Solutions [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Net discrete tax (benefits) expense related to tax settlements |  |  |  | $ (36)

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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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