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Acquisitions and Divestitures (Details) $ in Millions				3 Months Ended			6 Months Ended
Acquisitions and Divestitures (Details) $ in Millions	Dec. 01, 2019 USD ($) employee	Aug. 15, 2019 USD ($)	May 31, 2019 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Jan. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Restricted cash				$ 4					$ 55
Engineered Structures \| Small manufacturing facility in the United Kingdom
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, consideration								$ 12
Asset impairment charge (reversal)				$ (7)	$ 12
Engineered Structures \| Small Additive Manufacturing Facility Member [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, consideration			$ 1
Asset impairment charge (reversal)						$ 9
Loss on sale of business			$ 13
Proceeds from the sales of businesses		$ 13
Engine Products \| Forgings Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, consideration	$ 64
Asset impairment charge (reversal)					$ 6
Loss on sale of business	$ 46
Restricted cash									$ 53
Sales						$ 34	$ 66
Number of employees \| employee	540