Business Segment Information - Revenues and Income From Continuing Operations by Segment (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Mar. 29, 2019	Mar. 30, 2018	Mar. 29, 2019	Mar. 30, 2018
Segment Reporting Information [Line Items]
Revenue	$ 1,728	$ 1,562	$ 4,936	$ 4,507
Income From Continuing Operations Before Income Taxes
Non-operating income	46	46	140	136
Income from continuing operations before income taxes	283	208	811	661
Communication Systems
Segment Reporting Information [Line Items]
Revenue	568	479	1,577	1,377
Electronic Systems
Segment Reporting Information [Line Items]
Revenue	649	606	1,855	1,729
Space and Intelligence Systems
Segment Reporting Information [Line Items]
Revenue	514	482	1,515	1,410
Operating Segments \| Communication Systems
Segment Reporting Information [Line Items]
Revenue	568	479	1,577	1,377
Income From Continuing Operations Before Income Taxes
Segment operating income	172	144	474	404
Operating Segments \| Electronic Systems
Segment Reporting Information [Line Items]
Revenue	649	606	1,855	1,729
Income From Continuing Operations Before Income Taxes
Segment operating income	123	108	355	314
Operating Segments \| Space and Intelligence Systems
Segment Reporting Information [Line Items]
Revenue	514	482	1,515	1,410
Income From Continuing Operations Before Income Taxes
Segment operating income	87	83	265	250
Corporate eliminations
Segment Reporting Information [Line Items]
Revenue	(3)	(5)	(11)	(9)
Income From Continuing Operations Before Income Taxes
Segment operating income	(56)	(86)	(155)	(182)
Adjustment for deferred compensation				12
Corporate eliminations \| Air-to-ground Long Term Evolution (LTE) \| Other Restructuring
Income From Continuing Operations Before Income Taxes
Business charges in connection with transition and exit costs		45		45
Corporate eliminations \| Exelis
Income From Continuing Operations Before Income Taxes
Amortization of intangible assets	25	25	76	75
Corporate eliminations \| L3 Technologies, Inc.
Income From Continuing Operations Before Income Taxes
Merger-related transaction and integration costs	16		29
Segment Reconciling Items
Income From Continuing Operations Before Income Taxes
Pension adjustment	(47)	(46)	(140)	(138)
Non-operating income	46	46	140	136
Net interest expense	$ (42)	$ (41)	$ (128)	$ (123)

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Revenue and income from continuing operations before income taxes by segment

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation.

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