Business Segment Information - Revenues and Income From Continuing Operations by Segment (Details) - USD ($) $ in Millions	3 Months Ended
Sep. 28, 2018	Sep. 29, 2017
Segment Reporting Information [Line Items]
Revenue	$ 1,542	$ 1,410
Income From Continuing Operations Before Income Taxes
Non-operating income	47	46
Net interest expense	(43)	(41)
Income from continuing operations before income taxes	257	228
Communication Systems
Segment Reporting Information [Line Items]
Revenue	469	406
Electronic Systems
Segment Reporting Information [Line Items]
Revenue	589	541
Space and Intelligence Systems
Segment Reporting Information [Line Items]
Revenue	488	466
Operating Segments \| Communication Systems
Segment Reporting Information [Line Items]
Revenue	469	406
Income From Continuing Operations Before Income Taxes
Segment operating income	140	115
Operating Segments \| Electronic Systems
Segment Reporting Information [Line Items]
Revenue	589	541
Income From Continuing Operations Before Income Taxes
Segment operating income	115	109
Operating Segments \| Space and Intelligence Systems
Segment Reporting Information [Line Items]
Revenue	488	466
Income From Continuing Operations Before Income Taxes
Segment operating income	86	87
Corporate eliminations
Segment Reporting Information [Line Items]
Revenue	(4)	(3)
Unallocated corporate expense and corporate eliminations
Income From Continuing Operations Before Income Taxes
Segment operating income	(41)	(42)
Pension adjustment	(47)	(46)
Unallocated corporate expense and corporate eliminations \| Exelis
Income From Continuing Operations Before Income Taxes
Amortization of intangible assets	$ 25	$ 25

Cost of Goods and Services Sold and Operating Expenses

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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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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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The net amount of operating interest income (expense).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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