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 and Geographic Area Information - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) segment	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Mar. 31, 2020 USD ($)	Mar. 30, 2020
Segment Reporting Information [Line Items]
Number of reportable segments \| segment	4
Goodwill (A and P)	$ 4,102	$ 4,067	$ 4,186
Percentage of fair value in excess of carrying amount	50.00%
Engine Products
Segment Reporting Information [Line Items]
Goodwill (A and P)	$ 2,171	$ 2,164	$ 2,066	$ 17
Engineered Structures
Segment Reporting Information [Line Items]
Percentage of fair value in excess of carrying amount				15.00%	60.00%
Revenue Benchmark \| Customer Concentration Risk \| Aerospace
Segment Reporting Information [Line Items]
Concentration risk, percentage	69.00%	71.00%	70.00%
Revenue Benchmark \| Customer Concentration Risk \| Aerospace \| General Electric Company
Segment Reporting Information [Line Items]
Concentration risk, percentage	11.00%