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DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Narrative (Details)	6 Months Ended	12 Months Ended
	Jan. 03, 2020 USD ($) contract	Jan. 01, 2021 USD ($) contract	Jun. 28, 2019 USD ($)	Jun. 29, 2018 USD ($)	Dec. 16, 2020 USD ($)	Nov. 25, 2020 USD ($)	Nov. 27, 2019 USD ($)	Jun. 29, 2019 USD ($) contract
Derivative [Line Items]
Amounts recognized in earnings related to hedging firm commitments no longer qualified as fair value hedges	$ 0	$ 0	$ 0	$ 0
Accumulated comprehensive loss, net of tax	508,000,000	839,000,000
Treasury locks \| L3Harris
Derivative [Line Items]
Liabilities recognized in business combination								$ 35,000,000
Fair Value Hedging \| Foreign currency forward contracts
Derivative [Line Items]
Derivative notional amount		0
Fair Value Hedging \| Treasury locks
Derivative [Line Items]
Fair value of derivative liability	56,000,000
Cash Flow Hedges \| Foreign currency forward contracts
Derivative [Line Items]
Derivative notional amount	$ 511,000,000	488,000,000
Pre-tax loss from cash flow hedges recognized in other comprehensive income		12,000,000
Estimated amount of existing gains to be reclassified into earnings within the next 12 months		19,000,000
Cash Flow Hedges \| Treasury locks
Derivative [Line Items]
Derivative notional amount		$ 650,000,000
Number of open derivative contracts \| contract	2	0
Accumulated comprehensive loss, net of tax	$ 16,000,000	$ 58,000,000	$ 24,000,000
Cash Flow Hedges \| Treasury locks \| L3Harris
Derivative [Line Items]
Number of open derivative contracts \| contract								2
Fixed-rate debt
Derivative [Line Items]
Aggregate principal amount of debt redeemed							$ 400,000,000
Fixed-rate debt \| 4.95% notes, due February 15, 2021
Derivative [Line Items]
Debt interest rate	4.95%	4.95%
Aggregate principal amount of debt redeemed	$ 650,000,000
Fixed-rate debt \| 4.95% notes, due February 15, 2021 \| Treasury Rate
Derivative [Line Items]
Debt interest rate						4.95%
Fixed-rate debt \| 1.80% notes, due January 15, 2031
Derivative [Line Items]
Debt interest rate		1.80%				1.80%
Aggregate principal amount of debt redeemed						$ 650,000,000
Fixed-rate debt \| 1.80% notes, due January 15, 2031 \| Treasury Rate
Derivative [Line Items]
Debt interest rate						1.80%
Fixed-rate debt \| 2.7% notes, due April 27, 2020
Derivative [Line Items]
Debt interest rate	2.70%				2.70%
Aggregate principal amount of debt redeemed	$ 400,000,000				$ 400,000,000
Fixed-rate debt \| 2.7% notes, due April 27, 2020 \| Treasury Rate
Derivative [Line Items]
Debt interest rate							2.70%
Fixed-rate debt \| 2.90% notes, due December 15, 2029
Derivative [Line Items]
Debt interest rate							2.90%