Supplemental Balance Sheet Information - Property, Plant, and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Property, Plant, and Equipment
Property, Plant and Equipment, Gross	$ 1,372	$ 1,103
Finance Lease, Right-of-Use Asset, after Accumulated Amortization	198	77
Accumulated depreciation	(555)	(490)
Property, plant and equipment, net	817	613
Non-cash accruals	119	51
Depreciation	76	56	$ 52
Land
Property, Plant, and Equipment
Property, Plant and Equipment, Gross	130	96
Buildings
Property, Plant, and Equipment
Property, Plant and Equipment, Gross	607	412
Machinery and Equipment [Member]
Property, Plant, and Equipment
Property, Plant and Equipment, Gross	564	494
Construction in progress
Property, Plant, and Equipment
Property, Plant and Equipment, Gross	71	101
Assets Held under Capital and Finance Leases
Property, Plant, and Equipment
Property, Plant and Equipment, Gross	134	43
Land and Land Improvements	64	34
Finance Lease, Right-of-Use Asset, after Accumulated Amortization	198	77
Accumulated depreciation	(21)	(10)
Property, plant and equipment, net	$ 177	$ 67

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Future cash outflow to pay for purchases of fixed assets that have occurred.

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