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Goodwill and Other Intangible Assets - Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Line Items]
Impairment of goodwill (A and N)		$ 0	$ 0	$ 719,000,000
Amortization of intangible assets		70,000,000	81,000,000	$ 71,000,000
Minimum
Goodwill [Line Items]
Expected amortization for the year 2020		50,000,000
Expected amortization for the year 2021		0
Expected amortization for the year 2022		0
Expected amortization for the year 2023		0
Maximum
Goodwill [Line Items]
Expected amortization for the year 2020		60,000,000
Expected amortization for the year 2021		0
Expected amortization for the year 2022		0
Expected amortization for the year 2023		$ 0
Engineered Products and Forgings
Goodwill [Line Items]
Impairment of goodwill (A and N)			$ 719,000,000
Disks Assets Group
Goodwill [Line Items]
Intangible asset impairments	$ 197,000,000