Closing stock price.

No definition available.

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- Definition

Current convertible common stock price, which is 120% of the current conversion price. Used for calculating the conversion of its convertible debt as contained in the provisions of the Convertible Contingent Debt Securities, which is used under certain conditions to settle the principal in cash based on a 120% of the conversion price, and if the settlement amount exceeds the principal amount, the excess will be settled in cash or stock or a combination thereof, at the Company's option.

+ References

No definition available.

+ Details

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- Definition

Debt instrument convertible number of shares.

+ References

No definition available.

+ Details

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- Definition

Excess of current common stock price over common stock conversion price.

+ References

No definition available.

+ Details

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- Definition

Revolving Credit Maturity Date

+ References

No definition available.

+ Details

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- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031897-161870

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Details

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 5

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Debt - Components of Debt and Reconciliation to Carrying Amount of Long-Term Debt (Parenthetical) (Detail) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	9 Months Ended											3 Months Ended		9 Months Ended
	Sep. 27, 2013	Dec. 31, 2012	Sep. 27, 2013 CODES Due 2035 [Member]	Sep. 27, 2013 L-3 Communications Corporation's [Member] 3.95% Senior Notes due 2016 [Member]	Dec. 31, 2012 L-3 Communications Corporation's [Member] 3.95% Senior Notes due 2016 [Member]	Sep. 27, 2013 L-3 Communications Corporation's [Member] 5.20% Senior Notes due 2019 [Member]	Dec. 31, 2012 L-3 Communications Corporation's [Member] 5.20% Senior Notes due 2019 [Member]	Sep. 27, 2013 L-3 Communications Corporation's [Member] 4.75% Senior Notes due 2020 [Member]	Dec. 31, 2012 L-3 Communications Corporation's [Member] 4.75% Senior Notes due 2020 [Member]	Sep. 27, 2013 L-3 Communications Corporation's [Member] 4.95% Senior Notes due 2021 [Member]	Dec. 31, 2012 L-3 Communications Corporation's [Member] 4.95% Senior Notes due 2021 [Member]	Sep. 27, 2013 L-3 Communications Holdings, Inc. [Member]	Sep. 28, 2012 L-3 Communications Holdings, Inc. [Member]	Sep. 27, 2013 L-3 Communications Holdings, Inc. [Member]	Sep. 28, 2012 L-3 Communications Holdings, Inc. [Member]	Oct. 23, 2013 L-3 Communications Holdings, Inc. [Member] Subsequent Event [Member]	Sep. 27, 2013 L-3 Communications Holdings, Inc. [Member] CODES Due 2035 [Member]	Dec. 31, 2012 L-3 Communications Holdings, Inc. [Member] CODES Due 2035 [Member]
Debt Instrument [Line Items]
Interest rate on Senior Notes			3.00%	3.95%	3.95%	5.20%	5.20%	4.75%	4.75%	4.95%	4.95%						3.00%	3.00%
Borrowings under Amended and Restated Revolving Credit Facility	$ 1,000,000,000
Revolving Credit Facility expiry date	Feb. 03, 2017
Excess of current common stock price over common stock conversion price	120.00%
Common stock, shares	7.6
Current convertible common stock price																	$ 108.29
Conversion price of L-3 Holdings' CODES	$ 90.24																$ 90.24
Closing stock price																$ 95.98
Interest expense recognized												5,000,000	5,000,000	15,000,000	15,000,000
Carrying amount of the equity component (conversion feature)	$ 64,000,000	$ 64,000,000