Income tax benefit from tax loss related to divestiture.

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- Definition

Income taxes.

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No definition available.

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- Definition

Non cash income tax expense(benefit).

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No definition available.

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- Definition

Unrecognized tax benefits included in consolidated financial statement.

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No definition available.

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- Definition

Unrecognized tax benefits offset against deferred tax assets.

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No definition available.

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- Definition

The potential impact on the consolidated tax provision if unrecognized tax benefits were recognized at a given point in time.

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No definition available.

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- Definition

The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

+ References

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- Definition

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

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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- Definition

Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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- Definition

Amount of unrecognized tax benefits.

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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Income Taxes [Line Items]
Other tax credit carryforwards	$ 144,000,000
Undistributed earnings	1,700,000,000
Unrecognized tax benefits	22,000,000	$ 20,000,000	$ 159,000,000	$ 21,000,000
Unrecognized tax benefits, offset against deferred tax assets	13,000,000	14,000,000
Non cash income tax expense (benefit)	24,000,000	152,000,000
Accruals for penalties and interest	10,000,000	5,000,000
Total penalties and interest	5,000,000	2,000,000	2,000,000
Favorable impact on tax provision	22,000,000
Purification Solutions [Member]
Income Taxes [Line Items]
Income tax benefit from tax loss related to divestiture		137,000,000	$ 137,000,000
Other Liabilities [Member]
Income Taxes [Line Items]
Unrecognized tax benefits, recorded	9,000,000	6,000,000
Maximum [Member]
Income Taxes [Line Items]
Other tax credit carryforwards	$ 1,000,000
Maximum [Member] \| United States Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2023
Minimum [Member] \| United States Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2021
Foreign Jurisdictions [Member]
Income Taxes [Line Items]
NOLs	$ 35,000,000
Foreign Jurisdictions [Member] \| Maximum [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2023
Foreign Jurisdictions [Member] \| Minimum [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2006
State Tax Authorities [Member] \| Maximum [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2023
State Tax Authorities [Member] \| Minimum [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2018
U.S. Defined Benefit Plans [Member]
Income Taxes [Line Items]
Increased/(decreased) valuation in allowance	$ 494,000,000
U.S. Defined Benefit Plans [Member] \| Maximum [Member]
Income Taxes [Line Items]
Increased/(decreased) valuation in allowance		498,000,000
U.S. Defined Benefit Plans [Member] \| Minimum [Member]
Income Taxes [Line Items]
Increased/(decreased) valuation in allowance		$ (4,000,000)