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The amount of estimated penalties recognized in the period arising from income tax examinations.

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Legal Proceedings and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	6 Months Ended	12 Months Ended
	Apr. 30, 2015	Jun. 26, 2016	Dec. 31, 2015	Apr. 24, 2009
Legal Proceedings And Contingencies [Line Items]
Damages sought by plaintiff	$ 45
Statutory penalty	13
Total damages	$ 148
Liabilities recorded relative to environmental matters		$ 1,000	$ 1,000
Environmental costs eligible for future recovery		$ 897	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		$ 3,900	3,800
Third-party guarantees outstanding		$ 679	$ 678
Percentage of total guarantees that relate to guarantees of contractual performance of joint ventures		78.00%	79.00%
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