CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 02, 2021	Jul. 03, 2020	Jul. 02, 2021	Jul. 03, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 413	$ 278	$ 879	$ 472
Other comprehensive income (loss):
Foreign currency translation gain (loss), net of income taxes	15	7	(3)	(60)
Net unrealized gain (loss) on hedging derivatives, net of income taxes	2	13	7	(60)
Net unrecognized (loss) gain on postretirement obligations, net of income taxes	(2)	1	(2)	0
Other comprehensive income (loss) recognized during the period	15	21	2	(120)
Reclassification adjustments for losses included in net income	4	6	2	4
Other comprehensive income (loss), net of income taxes	19	27	4	(116)
Total comprehensive income	432	305	883	356
Comprehensive loss attributable to noncontrolling interests	0	5	2	28
Total comprehensive income attributable to L3Harris Technologies, Inc.	$ 432	$ 310	$ 885	$ 384