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Approximate percentage of expenditures to be reimbursed for certain remediation activities.

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Time period environmental costs and recovery of environmental costs are projected over.

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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

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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 and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	9 Months Ended	12 Months Ended
	Apr. 30, 2015	Sep. 25, 2016	Dec. 31, 2015	Apr. 24, 2009
Legal Proceedings And Contingencies [Line Items]
Liabilities recorded relative to environmental matters		$ 1,000	$ 1,000
Environmental costs eligible for future recovery		$ 896	858
Time period environmental costs and recovery of environmental costs are projected over, years		20 years
Percentage of expenditures that are reimbursed for certain remediation activities		50.00%
Outstanding letters of credit, surety bonds, and third-party guarantees		$ 3,800	3,800
Third-party guarantees outstanding		$ 694	$ 678
Percentage of total guarantees that relate to guarantees of contractual performance of joint ventures		55.00%	79.00%
Information Systems & Global Solutions \| Contractual performance
Legal Proceedings And Contingencies [Line Items]
Third-party guarantees outstanding		$ 278
Percentage of total guarantees that relate to guarantees of contractual performance of joint ventures		40.00%
Minimum
Legal Proceedings And Contingencies [Line Items]
Damages sought by plaintiff	$ 45
United Launch Alliance
Legal Proceedings And Contingencies [Line Items]
Percentage of ownership interest in affiliated entity		50.00%
Inventory supply agreement		$ 120
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