UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 29, 2018		Jun. 30, 2017		Jun. 29, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 379		$ 207		$ 587	$ 375
Other comprehensive income (loss):
Foreign currency translation adjustments	(72)		52		(39)	71
Unrealized lossess on hedging instruments (1)	(10)	[1]	0	[1]	(11)	0
Pension and postretirement benefit plans:
Amortization of net loss and prior service cost previously recognized (2)	13	[2]	10	[2]	27	19
Total other comprehensive (loss) income	(69)		62		(23)	90
Comprehensive income	310		269		564	465
Comprehensive income attributable to noncontrolling interests	(4)		(5)		(9)	(9)
Comprehensive income attributable to L3	$ 306		$ 264		$ 555	$ 456

[1] Net of income tax benefit of $3 million for each of the quarterly and first half periods ended June 29, 2018.

[2] Net of income taxes of $4 million and $5 million for the quarterly periods ended June 29, 2018 and June 30, 2017, respectively