Income taxes.

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Unrecognized tax benefits included in consolidated financial statement.

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Unrecognized tax benefits not included in consolidated financial statement.

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

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from state taxes.

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No definition available.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign tax credit carryforwards.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible tax credit carryforwards, classified as other.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible research tax credit carryforwards.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to foreign tax credit.

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

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

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

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Amount of unrecognized tax benefits.

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Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

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Amount of interest expense accrued for an underpayment of income taxes.

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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 ($) $ in Millions	1 Months Ended	12 Months Ended
	Jul. 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Oct. 01, 2019	Sep. 30, 2017
Income Taxes [Line Items]
Valuation allowance		$ 317	$ 124
NOLs		653
Foreign tax credit carry forwards		58	20
R&D credit carryforwards		44	43
Other business credit carryforwards		23	29
Increased/(decreased) valuation allowance			(45)
Other tax credit carryforwards		125
Undistributed earnings		1,631
Unrecognized tax benefits		23	27	$ 37		$ 36
Unrecognized tax benefits, recorded		14
Unrecognized tax benefits, not recorded		9
Accruals for penalties		1
Accruals for interest		3
Total penalties and interest		1	$ 2	$ 2
Favorable impact on tax provision		$ 23
Earliest Tax Year [Member] \| United States Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination		2017
Latest Tax Year [Member] \| United States Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination		2019
Non-U.S. Jurisdictions [Member]
Income Taxes [Line Items]
NOLs		$ 32
Increased/(decreased) valuation allowance		$ (32)
Non-U.S. Jurisdictions [Member] \| Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination		2003
Non-U.S. Jurisdictions [Member] \| Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination		2019
State Tax Authorities [Member] \| Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination		2005
State Tax Authorities [Member] \| Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination		2019
Specialty Fluids [Member]
Income Taxes [Line Items]
Operating losses subject to expiration		$ 16
U.S. Defined Benefit Plans [Member]
Income Taxes [Line Items]
Valuation allowance		253
NOLs		18
Foreign tax credit carry forwards		58
R&D credit carryforwards		44
State tax credits		19
Other business credit carryforwards		114
Increased/(decreased) valuation allowance		193
Net deferred tax assets		228
U.S. Defined Benefit Plans [Member] \| Originated in Prior Year [Member]
Income Taxes [Line Items]
Net deferred tax assets					$ 132
U.S. Defined Benefit Plans [Member] \| Originated in Current Year [Member]
Income Taxes [Line Items]
Net deferred tax assets		96
Minimum [Member]
Income Taxes [Line Items]
Foreign tax rate	90.00%
Maximum [Member] \| Non-U.S. Jurisdictions [Member]
Income Taxes [Line Items]
Other tax credit carryforwards		$ 1