CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2021	Apr. 03, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 466	$ 194
Other comprehensive loss:
Foreign currency translation loss, net of income taxes	(18)	(67)
Net unrealized gain (loss) on hedging derivatives, net of income taxes	5	(73)
Net unrecognized loss on postretirement obligations, net of income taxes	0	(1)
Other comprehensive loss recognized during the period	(13)	(141)
Less: reclassification adjustments for gains included in net income	(2)	(2)
Other comprehensive loss, net of income taxes	(15)	(143)
Total comprehensive income	451	51
Comprehensive loss attributable to noncontrolling interests	2	23
Total comprehensive income attributable to L3Harris Technologies, Inc.	$ 453	$ 74