CONDENSED CONSOLIDATED STATEMENT OF INCOME - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Oct. 02, 2020	Sep. 27, 2019	Oct. 02, 2020	Sep. 27, 2019
Income Statement [Abstract]
Revenue from product sales and services	$ 4,463	$ 4,431	$ 13,534	$ 8,024
Cost of product sales and services	(3,152)	(3,242)	(9,625)	(5,604)
Engineering, selling and administrative expenses	(817)	(999)	(2,484)	(1,658)
Business divestiture-related (losses) gains	(10)	229	(62)	229
Impairment of goodwill and other assets	0	0	(394)	0
Non-operating income	96	79	296	173
Interest income	4	9	12	10
Interest expense	(66)	(67)	(202)	(149)
Income from continuing operations before income taxes	518	440	1,075	1,025
Income taxes	(87)	(5)	(171)	(78)
Income from continuing operations	431	435	904	947
Discontinued operations, net of income taxes	(1)	0	(2)	(1)
Net income	430	435	902	946
Noncontrolling interests, net of income taxes	(4)	(6)	24	(6)
Net income attributable to L3Harris Technologies, Inc.	426	429	926	940
Amounts attributable to L3Harris Technologies, Inc. common shareholders
Income from continuing operations	427	429	928	941
Discontinued operations, net of income taxes	$ (1)	$ 0	$ (2)	$ (1)
Basic
Continuing operations (in dollars per share)	$ 2.00	$ 1.93	$ 4.31	$ 6.25
Discontinued operations (in dollars per share)	0	0	(0.01)	0
Basic (in dollars per share)	2.00	1.93	4.30	6.25
Diluted
Continuing operations (in dollars per share)	1.99	1.90	4.27	6.13
Discontinued operations (in dollars per share)	(0.01)	0	(0.01)	0
Diluted (in dollars per share)	$ 1.98	$ 1.90	$ 4.26	$ 6.13
Basic weighted average common shares outstanding (in shares)	213.4	222.6	215.5	150.6
Diluted weighted average common shares outstanding (in shares)	215.1	225.4	217.3	153.5