GOODWILL (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jan. 03, 2020	Jun. 28, 2019	Jun. 29, 2018
Goodwill [Roll Forward]
Beginning Balance	$ 5,340	$ 5,372	$ 5,366
Currency translation adjustments	12	(2)	6
Decrease from reclassification to assets of disposal group held for sale		(30)
Goodwill acquired	14,649
Ending Balance	20,001	5,340	5,372
Harris Night Vision \| Discontinued Operations, Held-for-sale or Disposed of by Sale
Goodwill [Roll Forward]
Beginning Balance	30
Ending Balance		30
Communication Systems
Goodwill [Roll Forward]
Beginning Balance	64	64	64
Currency translation adjustments	1		0
Decrease from reclassification to assets of disposal group held for sale		0
Goodwill acquired	5,704
Ending Balance	5,768	64	64
Space and Airborne Systems
Goodwill [Roll Forward]
Beginning Balance	3,737	3,739	3,733
Currency translation adjustments	4	(2)	6
Decrease from reclassification to assets of disposal group held for sale		0
Goodwill acquired	1,390
Ending Balance	5,131	3,737	3,739
Communication Systems
Goodwill [Roll Forward]
Beginning Balance	927	927	927
Currency translation adjustments	0		0
Decrease from reclassification to assets of disposal group held for sale		0
Goodwill acquired	3,316
Ending Balance	4,243	927	927
Aviation Systems
Goodwill [Roll Forward]
Beginning Balance	612	612	612
Currency translation adjustments	7	0	0
Decrease from reclassification to assets of disposal group held for sale		0
Goodwill acquired	4,239
Ending Balance	4,859	612	612
Other non-reportable business segments
Goodwill [Roll Forward]
Beginning Balance	0	30	30
Currency translation adjustments	0	0	0
Decrease from reclassification to assets of disposal group held for sale		(30)
Goodwill acquired	0
Ending Balance	$ 0	$ 0	$ 30

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of transfers into (out of) an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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