Business Segment Information - Revenues and Income From Continuing Operations by Segment (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Dec. 28, 2018	Dec. 29, 2017	Dec. 28, 2018	Dec. 29, 2017
Segment Reporting Information [Line Items]
Revenue	$ 1,666	$ 1,535	$ 3,208	$ 2,945
Income From Continuing Operations Before Income Taxes
Non-operating income	47	44	94	90
Net interest expense	(43)	(41)	(86)	(82)
Income from continuing operations before income taxes	271	225	528	453
Communication Systems
Segment Reporting Information [Line Items]
Revenue	540	492	1,009	898
Electronic Systems
Segment Reporting Information [Line Items]
Revenue	617	582	1,206	1,123
Space and Intelligence Systems
Segment Reporting Information [Line Items]
Revenue	513	462	1,001	928
Operating Segments \| Communication Systems
Segment Reporting Information [Line Items]
Revenue	540	492	1,009	898
Income From Continuing Operations Before Income Taxes
Segment operating income	162	145	302	260
Operating Segments \| Electronic Systems
Segment Reporting Information [Line Items]
Revenue	617	582	1,206	1,123
Income From Continuing Operations Before Income Taxes
Segment operating income	117	97	232	206
Operating Segments \| Space and Intelligence Systems
Segment Reporting Information [Line Items]
Revenue	513	462	1,001	928
Income From Continuing Operations Before Income Taxes
Segment operating income	92	80	178	167
Corporate eliminations
Segment Reporting Information [Line Items]
Revenue	(4)	(1)	(8)	(4)
Unallocated corporate expense and corporate eliminations
Income From Continuing Operations Before Income Taxes
Segment operating income	(58)	(54)	(99)	(96)
Pension adjustment	(46)	(46)	(93)	(92)
Adjustment for deferred compensation		12		12
Unallocated corporate expense and corporate eliminations \| Exelis
Income From Continuing Operations Before Income Taxes
Amortization of intangible assets	26	$ 25	51	$ 50
Unallocated corporate expense and corporate eliminations \| L3 Technologies, Inc.
Income From Continuing Operations Before Income Taxes
Merger-related transaction and integration costs	$ 13		$ 13

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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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The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

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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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