Effective Income Tax Rate Reconciliation, Prior Year Deferred Income Taxes, Amount

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Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Net Noncontrolling Interests, Amount

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Schedule Of Income Taxes [Line Items]

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of current and deferred federal income tax expense (benefit) attributable to income (loss) from continuing operations.

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Amount of current and deferred foreign income tax expense (benefit) attributable to income (loss) from continuing operations.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount 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 revisions of previously reported income tax expense (benefit).

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Amount 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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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The amount of cash received during the period as refunds for the overpayment of taxes.

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Income Taxes (Unaudited) (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended		9 Months Ended		12 Months Ended
Income Taxes (Unaudited) (Details) - USD ($) $ in Millions	Oct. 31, 2020	Jul. 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2021
Schedule Of Income Taxes [Line Items]
U.S. operations					$ 56	$ 73
International operations					(389)	(254)
Total			$ (297)	$ (91)	(333)	(181)
Tax charge resulting from prior period tax positions					21
Tax charge resulting from prior period tax positions, net noncontrolling interests					$ 17
Tax charge resulting from prior period deferred tax positions						$ 49
Consolidated effective income tax rate (percent)					102.00%	302.00%
Proceeds from Income Tax Refunds		$ 221
Forecast
Schedule Of Income Taxes [Line Items]
Proceeds from Income Tax Refunds							$ 23
Foreign Tax Authority [Member]
Schedule Of Income Taxes [Line Items]
Tax credit					$ 53
State and Local Jurisdiction [Member]
Schedule Of Income Taxes [Line Items]
Tax credit						$ 24
Subsequent event
Schedule Of Income Taxes [Line Items]
Proceeds from Income Tax Refunds	$ 24