Acquisitions and Dispositions Textuals Abstract.

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- Definition

Amount of loss on sale of business, net of income taxes.

+ Details

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- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d

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- Definition

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 Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph r(2, 3)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 54

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 55

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- Definition

The pro forma net income (loss) for the period as if the business combination or combinations had been completed at the beginning of a period

+ References

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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

+ References

+ Details

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- Definition

Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 52
-Subparagraph c

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 53
-Subparagraph d

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- Definition

Amount of sales or other form of revenues attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 144
-Paragraph 47
-Subparagraph c

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Acquisitions and Dispositions (Details) (USD $) In Millions, except Per Share data	3 Months Ended		6 Months Ended
	Apr. 01, 2011	Jun. 25, 2010	Jun. 25, 2010	Jul. 01, 2011
Unaudited Pro Forma Statements of Operations Data
Pro forma net sales		$ 4,002	$ 7,720
Pro forma net income attributable to L-3		234	462
Pro forma diluted earnings per share		$ 2.00	$ 3.93
Acquisitions and Dispositions (Textuals)
Aggregate purchase price of acquisition				13
Amount of goodwill recognized				9
Amount of loss on sale of business, net of income taxes	approximately $1 million
Annual revenue from business	$ 8