CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 03, 2020	Jun. 28, 2019	Jul. 03, 2020	Jun. 28, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 278	$ 268	$ 472	$ 511
Other comprehensive income (loss):
Foreign currency translation gain (loss), net of income taxes	7	(2)	(60)	1
Net unrealized gain (loss) on hedging derivatives, net of income taxes	13	(11)	(60)	(19)
Net unrecognized gain (loss) on postretirement obligations, net of income taxes	1	(477)	0	(478)
Other comprehensive income (loss), net of income taxes	21	(490)	(120)	(496)
Total comprehensive income (loss)	299	(222)	352	15
Comprehensive loss attributable to noncontrolling interests	5	0	28	0
Total comprehensive income (loss) attributable to L3Harris Technologies, Inc.	$ 304	$ (222)	$ 380	$ 15