Information on Business Segments - Additional Information (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) segment	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Segment Reporting Information [Line Items]
Number of business segments \| segment	4
Equity method investments	$ 784	$ 1,200
Net gain on divestiture of business segment	$ (55)	$ 0	$ 0
F-35 Program \| Net Sales \| Product Concentration Risk \| Aeronautics
Segment Reporting Information [Line Items]
Net sales for the F-35 program representing total consolidated net sales (as a percent)	28.00%	27.00%	27.00%
United Launch Alliance
Segment Reporting Information [Line Items]
Percentage of ownership interest in affiliated entity	50.00%
Equity method investments	$ 691	$ 709

Program net sales as percent of total net sales.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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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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