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Acquisitions and Divestitures (Details) $ in Millions			3 Months Ended				12 Months Ended
Acquisitions and Divestitures (Details) $ in Millions	Dec. 01, 2019 USD ($) segment	Aug. 15, 2019 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jun. 01, 2021 USD ($)	Jan. 31, 2020 USD ($)	May 31, 2019 USD ($)
Business Acquisition [Line Items]
Asset impairment charges							$ 15	$ 5	$ 442
Restructuring and other charges							90	182	582
Restricted cash							$ 2	1	55
Small Additive Manufacturing Facility \| Engineered Structures
Business Acquisition [Line Items]
Consideration												$ 1
Proceeds from the sales of businesses		$ 13
Asset impairment charges									10
Gain (loss) on disposition of business									13
Forgings Business \| Engineered Structures
Business Acquisition [Line Items]
Consideration	$ 64
Gain (loss) on disposition of business									46
Restructuring and other charges								$ 5
Restricted cash									53
Sales									$ 116
Number of employees \| segment	540
Disposed of by Sale \| Small Manufacturing Facility In France \| Fastening Systems
Business Acquisition [Line Items]
Consideration										$ 10
Proceeds from the sales of businesses			$ 8
Asset impairment charges				$ 4
Disposed of by Sale \| Small Manufacturing Facility In The United Kingdom \| Engineered Structures
Business Acquisition [Line Items]
Consideration											$ 12
Asset impairment charges					$ 7	$ 12