Discontinued operations businesses expected to be disposed within certain years.

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- Definition

Minimum percentage of estimated fair value of reporting unit to be less than carrying amount of goodwill.

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No definition available.

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- Definition

Period Required For One Quantitative Impairment Test To Be Performed For Each Reporting Unit

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No definition available.

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- Definition

Separation Transaction, Number Of Independent, Publicly-Traded Companies Formed

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No definition available.

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Summary Of Significant Accounting Policies [Line Items]

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No definition available.

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- Definition

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.

+ References

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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

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

+ References

No definition available.

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- Definition

The cash outflow from advancing money to an affiliate (an entity that is related but not strictly controlled by the entity).

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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- Definition

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

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No definition available.

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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Summary of Significant Accounting Policies - Additional Information (Details)		3 Months Ended	12 Months Ended
	Apr. 01, 2020 company	Jun. 30, 2018 USD ($)	Dec. 31, 2020 USD ($) reporting_unit segment	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Mar. 31, 2020	Mar. 30, 2020
Summary Of Significant Accounting Policies [Line Items]
Number of independent, publicly-traded companies resulting from proposed separation transaction \| company	2
Number of new segments \| segment			4
Capital expenditures			$ 267,000,000	$ 641,000,000	$ 768,000,000
Retained earnings (A)			$ 364,000,000	113,000,000
Number of reporting units \| reporting_unit			4
Minimum percentage of estimated fair value of reporting unit to be less than carrying amount of goodwill			50.00%
Period required for impairment testing of reporting units			3 years
Percentage of fair value in excess of carrying amount			50.00%
Impairment of goodwill (A and N)			$ 0	2,000,000
Advance payment			$ 85,000,000	97,000,000
Businesses expected to be disposed within, years			1 year
Revision of Prior Period, Error Correction, Adjustment
Summary Of Significant Accounting Policies [Line Items]
Capital expenditures				$ 55,000,000
Retained earnings (A)					$ 16,000,000
Aerospace \| Revenue Benchmark \| Customer Concentration Risk
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage			69.00%	71.00%	70.00%
Disks Asset Group
Summary Of Significant Accounting Policies [Line Items]
Impairment of goodwill (A and N)		$ 0
Engineered Structures
Summary Of Significant Accounting Policies [Line Items]
Percentage of fair value in excess of carrying amount						15.00%	60.00%