Divestitures and Acquisitions - Statement of Operations Data Classified as Discontinued Operations (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 25, 2016	Mar. 27, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on sale of business		$ (22)
NSS [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on sale of business	$ 64

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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