Business Segments - Revenues and Income From Continuing Operations by Segment (Details) $ in Millions	3 Months Ended	6 Months Ended
Dec. 29, 2017 USD ($)	Dec. 30, 2016 USD ($)	Dec. 29, 2017 USD ($) segment	Dec. 30, 2016 USD ($)
Income From Continuing Operations Before Income Taxes
Revenue	$ 1,535	$ 1,449	$ 2,948	$ 2,869
Segment operating income	272	277	544	523
Non-operating income (loss)	(2)	1	(2)	2
Net interest expense	(41)	(43)	(82)	(87)
Income from continuing operations before income taxes	229	235	$ 460	438
Number of remaining segments \| segment			3
Operating Segments \| Communication Systems
Income From Continuing Operations Before Income Taxes
Revenue	489	413	$ 899	843
Segment operating income	144	121	262	239
Operating Segments \| Electronic Systems
Income From Continuing Operations Before Income Taxes
Revenue	584	570	1,124	1,107
Segment operating income	101	134	210	245
Operating Segments \| Space and Intelligence Systems
Income From Continuing Operations Before Income Taxes
Revenue	465	468	931	921
Segment operating income	81	76	168	155
Corporate eliminations
Income From Continuing Operations Before Income Taxes
Revenue	(3)	(2)	(6)	(2)
Segment operating income	1	(1)	0	(2)
Unallocated corporate income (expense)
Income From Continuing Operations Before Income Taxes
Segment operating income	(55)	(53)	(96)	(114)
Adjustment for deferred compensation	12		12
Unallocated corporate income (expense) \| Exelis
Income From Continuing Operations Before Income Taxes
Business combination, integration and other costs	$ 25	13	$ 50	30
Amortization of intangible assets		$ 28		$ 55

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
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- Definition

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.

+ References

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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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- Definition

The net amount of operating interest income (expense).

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The net result for the period of deducting operating expenses from operating revenues.

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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