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SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details) engineer in Thousands, employee in Thousands, $ in Millions			6 Months Ended	12 Months Ended
	Sep. 13, 2019 USD ($)	Jun. 29, 2019	Jan. 03, 2020 USD ($) employee engineer site country	Jun. 28, 2019 USD ($)	Jun. 29, 2018 USD ($)	Jun. 30, 2017 USD ($)	Dec. 29, 2017
Business Combination, Separately Recognized Transactions [Line Items]
Number of countries in which entity operates \| country			130
Number of employees \| employee			50
Number of engineers \| engineer			20
Proceeds from sales of businesses, net			$ 343	$ 0	$ 0	$ 1,014
Internal use software, useful life minimum			3 years
Internal use software, useful life maximum			10 years
Threshold for separate line item reporting of total current assets or total assets in Consolidated Balance Sheets			5.00%	5.00%			5.00%
Threshold for separate line item reporting of total current liabilities or total liabilities in Consolidated Balance Sheet			5.00%	5.00%			5.00%
Amortization period for contract costs			1 year
Revenue recognized from performance obligations satisfied in previous periods			$ 98	$ 59	$ 43	$ 45
Number of sites with future environmental liabilities \| site			84
Number of sites owned \| site			8
Number of sites associated with former locations or operations \| site			66
Number of treatment or disposal sites not owned \| site			10
Accrual for environment loss contingencies			$ 115
L3Harris
Business Combination, Separately Recognized Transactions [Line Items]
Exchange ratio		1.30
L3Harris \| Harris Night Vision \| Discontinued Operations, Disposed of by Sale
Business Combination, Separately Recognized Transactions [Line Items]
Cash price on sale of business	$ 350
Proceeds from sales of businesses, net	343
L3Harris \| Former Harris Shareholders
Business Combination, Separately Recognized Transactions [Line Items]
Percentage of voting interests acquired		54.00%
L3Harris \| Former L3 Shareholders
Business Combination, Separately Recognized Transactions [Line Items]
Percentage of voting interests acquired		46.00%
Maximum \| Building
Business Combination, Separately Recognized Transactions [Line Items]
Property, plant and equipment, useful life			45 years
Maximum \| Machinery and Equipment
Business Combination, Separately Recognized Transactions [Line Items]
Property, plant and equipment, useful life			10 years
Minimum \| Building
Business Combination, Separately Recognized Transactions [Line Items]
Property, plant and equipment, useful life			2 years
Minimum \| Machinery and Equipment
Business Combination, Separately Recognized Transactions [Line Items]
Property, plant and equipment, useful life			2 years
Other non-reportable business segments \| L3Harris \| Harris Night Vision \| Discontinued Operations, Disposed of by Sale
Business Combination, Separately Recognized Transactions [Line Items]
Cash price on sale of business	350
Proceeds from sales of businesses, net	$ 343
Other current assets
Business Combination, Separately Recognized Transactions [Line Items]
Capitalized costs to obtain or fulfill a contract			$ 14
Other non-current assets
Business Combination, Separately Recognized Transactions [Line Items]
Capitalized costs to obtain or fulfill a contract			$ 48