CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jan. 03, 2020	Dec. 31, 2021	Jan. 01, 2021	Jun. 28, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 834	$ 1,842	$ 1,086	$ 949
Other comprehensive income (loss):
Foreign currency translation (loss) gain, net of income taxes	25	(63)	16	(7)
Net unrealized loss on hedging derivatives, net of income taxes	(17)	(3)	(31)	(18)
Net unrecognized gain (loss) on postretirement obligations, net of income taxes	178	758	(313)	(480)
Other comprehensive income (loss), recognized during the period	186	692	(328)	(505)
Reclassification adjustments for losses (gains) included in net income	13	1	(3)	0
Other comprehensive income, net of income taxes	199	693	(331)	(505)
Total comprehensive income	1,033	2,535	755	444
Comprehensive loss (income) attributable to noncontrolling interests	(12)	4	33	0
Total comprehensive income attributable to L3Harris Technologies, Inc.	$ 1,021	$ 2,539	$ 788	$ 444