Debt - Redemptions of Senior Subordinated Notes (Detail) (USD $)	0 Months Ended	12 Months Ended
	Jul. 26, 2012	Dec. 31, 2014	Dec. 31, 2012
Debt Instrument [Line Items]
Debt Retirement Charge			$ (13,000,000)
L-3 Communications Corporation [Member]
Debt Instrument [Line Items]
Debt Retirement Charge			(13,000,000)
Redemption Price % of Principal		101.00%
L-3 Communications Corporation [Member] | 6 3/8% Senior Subordinated Notes due October 15, 2015 [Member]
Debt Instrument [Line Items]
Redemption Date		Oct. 15, 2012
Principal Amount Redeemed			250,000,000
Debt Retirement Charge			5,000,000
Redemption Price % of Principal			101.063%
L-3 Communications Corporation [Member] | 6 3/8% Senior Subordinated Notes Due October 15, 2015 [Member]
Debt Instrument [Line Items]
Redemption Date		Jul. 26, 2012
Principal Amount Redeemed	250,000,000		250,000,000
Debt Retirement Charge			$ 8,000,000
Redemption Price % of Principal			102.125%