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.

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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=116825942&loc=d3e330036-122817

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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- Definition

The amount of income taxes from which a reporting entity is exempt or for which it will receive a reduction in income taxes as a result of the income tax holiday granted by the taxing jurisdiction.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330215-122817

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- Definition

Per share amount effect of the income tax benefit resulting from the income tax holidays granted by taxing jurisdictions.

+ References

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4297-108586

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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=84230637&loc=d3e32639-109319

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- Definition

Amount of expense 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (b)
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Income Taxes - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Income Tax [Line Items]
Federal statutory tax rate			21.00%	21.00%	24.50%	35.00%
EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRateNew				21.00%
Tax Cuts and Jobs Act, Income Tax Expense (Benefit)				$ 50	$ (640)
OtherTaxExpenseBenefitRelatedtoHistoricUnremittedForeignEarnings	$ 138	$ 67
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	624		$ 719	624	632
Unrecognized tax benefits interest and penalties reflected in current year			1	26	20
Tax reductions related to tax holidays			$ (136)	$ (43)	$ (107)
Income Tax Holiday, Income Tax Benefits Per Share			$ (0.48)	$ (0.16)	$ (0.40)
Income taxes paid, net			$ 518	$ 536	$ 235
Deferred Income Taxes and Other
Income Tax [Line Items]
Indemnification liability, non-current	$ 164			$ 164