The annual statutory tax rate effective upon new U.S. tax legislation.

No definition available.

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- Definition

Income Tax.

+ References

No definition available.

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- Definition

Indemnification Liability, Non-current

+ References

No definition available.

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- Definition

OtherTaxExpenseBenefitRelatedtoHistoricUnremittedForeignEarnings

+ References

No definition available.

+ Details

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.Fact.4)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319

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- Definition

Amount of income tax expense (benefit) from effect of Tax Cuts and Jobs Act.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32639-109319

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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Jun. 30, 2019	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Income Tax [Line Items]
EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRateNew				21.00%
Federal statutory tax rate		21.00%	21.00%	21.00%	35.00%
Tax Cuts and Jobs Act, Income Tax Expense (Benefit)				$ 50
OtherTaxExpenseBenefitRelatedtoHistoricUnremittedForeignEarnings	$ 67	$ 138
Deferred Income Taxes and Other
Income Tax [Line Items]
Indemnification liability, non-current		$ 119