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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to disposition of asset. Includes, but is not limited to, intra-entity transfer of asset other than inventory.

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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 other adjustments.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Income Taxes Other Tax Matters (Details) - USD ($) $ in Millions	3 Months Ended				12 Months Ended			24 Months Ended
	Sep. 30, 2021	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020
Other Tax Matters [Line Items]
Intercompany intellectual property transfer	$ 417				$ 417	$ 0	$ 0
Restructuring and impairment costs					242	783	235
Restructuring charges, tax					39	(48)
Mark-to-market gain (loss)					402	(274)	(618)
Mark-to-market gain(loss), tax					93	(65)	(130)
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount		$ 30		$ (76)
Transaction and integration costs						135	317
Release of tax indemnification reserve			$ (226)				(226)
Transaction and Integration Costs, Tax						18	35
Global Products
Other Tax Matters [Line Items]
Restructuring charges, tax							53
Impairment of Long-Lived Assets to be Disposed of						$ 15	$ 235	$ 250
2021 Restructuring Plan
Other Tax Matters [Line Items]
Restructuring and impairment costs					242
2021 Restructuring Plan \| Global Products
Other Tax Matters [Line Items]
Restructuring and impairment costs					$ 91