Unaudited Pro Forma Statements of Operations Data (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 28, 2012	Sep. 30, 2011	Sep. 28, 2012	Sep. 30, 2011
Business Acquisition [Line Items]
Pro forma net sales	$ 3,295	$ 3,377	$ 9,688	$ 9,824
Pro forma income from continuing operations	195	218	574	620
Pro forma net income attributable to L-3	$ 192	$ 239	$ 599	$ 692
Pro forma diluted earnings per share from continuing operations	$ 1.98	$ 2.06	$ 5.79	$ 5.71
Pro forma diluted earnings per share	$ 1.97	$ 2.28	$ 6.07	$ 6.44

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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Pro forma diluted earnings per share, which is commonly presented in initial public offerings.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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