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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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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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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

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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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Segment Information - Narrative (Details) $ in Millions	9 Months Ended
Segment Information - Narrative (Details) $ in Millions	Sep. 30, 2020 USD ($) segment	Mar. 31, 2020	Dec. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments \| segment	4
Goodwill	$ 4,072		$ 4,067
Revenue Benchmark \| Customer Concentration Risk \| Aerospace
Segment Reporting Information [Line Items]
Concentration risk, percentage	70.00%
Revenue Benchmark \| Customer Concentration Risk \| Aerospace \| General Electric Company
Segment Reporting Information [Line Items]
Concentration risk, percentage	11.00%
Engineered Structures
Segment Reporting Information [Line Items]
Goodwill			$ 17
Margin between fair value of reporting unit and carrying value (percent)	20.00%	15.00%	60.00%
Engine Products
Segment Reporting Information [Line Items]
Goodwill			$ (17)