CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 28, 2013		Jun. 29, 2012		Jun. 28, 2013		Jun. 29, 2012
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 186		$ 208		$ 380		$ 411
Other comprehensive (loss) income:
Foreign currency translation adjustments	(18)		(47)		(52)		(18)
Unrealized (losses) gains on hedging instruments	(1)	[1]	(1)	[1]	(4)	[1]	2	[1]
Pension and postretirement benefit plans:
Amortization of net loss and prior service cost previously recognized	14	[2]	11	[2]	27	[2]	22	[2]
Total other comprehensive (loss) income:	(5)		(37)		(29)		6
Comprehensive income	181		171		351		417
Less: Comprehensive income attributable to noncontrolling interests	1		3		2		5
Comprehensive income attributable to L-3	$ 180		$ 168		$ 349		$ 412

[1] Amounts are net of income tax benefits of $1 million for both of the quarterly periods ended June 28, 2013 and June 29, 2012, and an income tax benefit of $2 million and income tax of $1 million for the first half periods ended June 28, 2013 and June 29, 2012, respectively.

[2] Amounts are net of income taxes of $7 million and $6 million for the quarterly periods ended June 28, 2013 and June 29, 2012, respectively, and $16 million and $12 million for the first half periods ended June 28, 2013 and June 29, 2012, respectively.