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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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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Number of pending claims pertaining to a loss contingency.

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Carrying amount as of the balance sheet date of known and reasonably estimable amounts of recoveries from third-parties pertaining to an entity's environmental remediation obligations. An entity's balance sheet may include several assets that relate to an environmental remediation obligation. Among them are the following: a. Receivables from other potentially responsible parties that are not providing initial funding; b. anticipated recoveries from insurers; and c. anticipated recoveries from prior owners as a result of indemnification agreements.

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Legal Proceedings, Commitments and Contingencies (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Nov. 30, 2017 lawsuit	Apr. 24, 2009 USD ($)
Legal Proceedings And Contingencies [Line Items]
Damages sought by plaintiff	$ 52
Liabilities recorded relative to environmental matters	920	$ 1,000
Environmental costs eligible for future recovery	$ 799	870
Time period environmental costs and recovery of environmental costs are projected over, years	20 years
Total rental expense under operating leases	$ 169	202	$ 195
Future minimum lease commitments, total	623
Future minimum lease commitments, due in 2018	162
Future minimum lease commitments, due in 2019	154
Future minimum lease commitments, due in 2020	116
Future minimum lease commitments, due in 2021	82
Future minimum lease commitments, due in 2022	54
Future minimum lease commitments, due in later years	55
Outstanding letters of credit, surety bonds, and third-party guarantees	3,300	3,700
Third-party guarantees outstanding	$ 750	$ 709
Percentage of total guarantees that relate to guarantees of contractual performance of joint ventures	62.00%	56.00%
Total equity method investment	$ 1,400	$ 1,400
United Launch Alliance
Legal Proceedings And Contingencies [Line Items]
Percentage of ownership interest in affiliated entity	50.00%
Inventory supply agreement	$ 120
Total equity method investment	794	$ 788
N.Y. Metropolitan Transportation Authority
Legal Proceedings And Contingencies [Line Items]
Damages sought by plaintiff	190
Contract value					$ 323
Contract payments received to date	241
Claims for monetary damages against the plaintiff	$ 95
Sikorsky Aircraft Corporation
Legal Proceedings And Contingencies [Line Items]
Number of pending lawsuits \| lawsuit				2