Business Segment Information - Revenues and Income From Continuing Operations by Segment (Details) - USD ($) $ in Millions	3 Months Ended
Sep. 27, 2019	Sep. 28, 2018
Segment Reporting Information [Line Items]
Revenue	$ 4,431	$ 1,542
Income From Continuing Operations Before Income Taxes
Other business activities and non-reportable business segments	(1)	0
Gain on sale of business	229	0
Non-operating income	79	47
Income from continuing operations before income taxes	440	257
L3Harris
Segment Reporting Information [Line Items]
Revenue		1,542
Income From Continuing Operations Before Income Taxes
Amortization of acquisition-related intangibles	(125)
Additional cost of sales related to fair value step-up in inventory sold	92
Exelis
Income From Continuing Operations Before Income Taxes
Amortization of acquisition-related intangibles		(29)
Other non-reportable business segments
Segment Reporting Information [Line Items]
Revenue	23	39
Operating segments \| Integrated Mission Systems
Segment Reporting Information [Line Items]
Revenue	1,303	12
Income From Continuing Operations Before Income Taxes
Segment operating income	180	2
Operating segments \| Space and Airborne Systems
Segment Reporting Information [Line Items]
Revenue	1,162	840
Income From Continuing Operations Before Income Taxes
Segment operating income	226	156
Operating segments \| Communication Systems
Segment Reporting Information [Line Items]
Revenue	1,032	480
Income From Continuing Operations Before Income Taxes
Segment operating income	234	137
Operating segments \| Aviation Systems
Segment Reporting Information [Line Items]
Revenue	948	172
Income From Continuing Operations Before Income Taxes
Segment operating income	127	24
Corporate eliminations
Segment Reporting Information [Line Items]
Revenue	(37)	(1)
Segment reconciling items
Income From Continuing Operations Before Income Taxes
Other business activities and non-reportable business segments	(93)	6
Merger, acquisition and divestiture-related expenses and losses	(281)	0
Amortization of acquisition-related intangibles	(123)	(25)
Gain on sale of business	229	0
Pension adjustment	(80)	(47)
Non-operating income	79	47
Net interest expense	(58)	(43)
Gain on sale of asset group	12
Segment reconciling items \| Restatement Adjustment
Income From Continuing Operations Before Income Taxes
Non-cash cumulative adjustment to lease expense	12
Segment reconciling items \| L3Harris
Income From Continuing Operations Before Income Taxes
Amortization of acquisition-related intangibles	(98)
Additional cost of sales related to fair value step-up in inventory sold	92
Segment reconciling items \| Exelis
Income From Continuing Operations Before Income Taxes
Amortization of acquisition-related intangibles	$ (25)	$ (25)

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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