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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Change in recurring obligations of a business that arise from the acquisition of merchandise, materials, supplies and services used in the production and sale of goods and services.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Basis of Presentation (Details) $ in Millions		3 Months Ended		6 Months Ended
Basis of Presentation (Details) $ in Millions	Apr. 01, 2020 company	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)
Concentration Risk [Line Items]
Number of independent, publicly-traded companies resulting from proposed separation transaction \| company	2
Capital expenditures		$ 55	$ 152
Decrease to accounts payable, trade		(26)	132
Tax misstatement recorded to retained earnings		$ 443			$ 364
Revision of Prior Period, Error Correction, Adjustment
Concentration Risk [Line Items]
Capital expenditures			83	$ 83
Decrease to accounts payable, trade			$ 83	$ 83
Tax misstatement recorded to retained earnings						$ 16
Aerospace \| Revenue Benchmark \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage		60.00%	73.00%