BUSINESS COMBINATION - Merger-related Charges (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jan. 03, 2020	Jan. 01, 2021	Jun. 28, 2019	Jun. 29, 2018
Business Acquisition [Line Items]
Restructuring charges, recognized as incurred	$ 117	$ 26
L3Harris
Business Acquisition [Line Items]
Equity award acceleration charges, recognized upon change in control	70	0	$ 0
Transaction costs, recognized as incurred	83	0	31
Additional cost of sales related to the fair value step-up in inventory sold	142	31	0
Restructuring charges, recognized as incurred	117	10	0	$ 0
Facility consolidation costs	48	0	0
Integration costs, recognized as incurred	72	130	34
Total L3Harris Merger-related charges	$ 532	$ 171	$ 65

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Business Combination, Facility Consolidation Costs

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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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. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

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