Goodwill, Measurement Input

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

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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No definition available.

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- Definition

Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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- Definition

Percentage of fair value of reporting unit in excess of carrying amount.

+ References

No definition available.

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Goodwill and Other Intangible Assets - Goodwill (Details)		3 Months Ended		12 Months Ended
	Jul. 12, 2018 USD ($)	Dec. 31, 2020 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Mar. 31, 2020 USD ($)	Jun. 03, 2019 USD ($)
Goodwill [Line Items]
Goodwill		$ 240,700,000		$ 240,700,000	$ 525,800,000
Period increase (decrease) in goodwill				(285,100,000)
Impairment of goodwill			$ (287,000,000.0)	(287,000,000.0)	0	$ 0
Accumulated goodwill impairment		$ 528,000,000.0		$ 528,000,000.0	$ 241,000,000.0	241,000,000.0
Weighted average cost of capital \| Fair Value, Inputs, Level 3 [Member]
Goodwill [Line Items]
Goodwill, fair value measurement input		0.117		0.117
Long-term growth rate \| Fair Value, Inputs, Level 3 [Member] \| Minimum
Goodwill [Line Items]
Goodwill, fair value measurement input		0.03		0.03
Long-term growth rate \| Fair Value, Inputs, Level 3 [Member] \| Maximum
Goodwill [Line Items]
Goodwill, fair value measurement input		0.035		0.035
Addaero Manufacturing [Member]
Goodwill [Line Items]
Goodwill						6,000,000.0
Payments to Acquire Businesses, Gross	$ 10,000,000.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles						$ 2,000,000.0
High Performance Materials & Components
Goodwill [Line Items]
Goodwill		$ 240,700,000		$ 240,700,000
Impairment of goodwill		0
Goodwill, Foreign Currency Translation Gain (Loss)				1,900,000
Forged Products
Goodwill [Line Items]
Goodwill		$ 173,400,000		$ 173,400,000			$ 460,400,000	$ 10,400,000
Percentage of fair value in excess of carrying value		2.00%		2.00%	30.00%
Forged Products \| Weighted average cost of capital \| Fair Value, Inputs, Level 3 [Member]
Goodwill [Line Items]
Goodwill, fair value measurement input			0.116
Forged Products \| Long-term growth rate \| Fair Value, Inputs, Level 3 [Member]
Goodwill [Line Items]
Goodwill, fair value measurement input			0.035
Specialty Materials [Member]
Goodwill [Line Items]
Goodwill		$ 67,300,000		$ 67,300,000