PENSION AND OTHER POSTRETIREMENT BENEFITS - Roll Forward of Plan Assets and Funded Status (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jan. 03, 2020	Jan. 01, 2021	Jun. 29, 2018
Change in plan assets
Plan assets at beginning of fiscal year		$ 8,892
Plan assets acquired in L3Harris Merger	$ 3,251	0
Actual return on plan assets	566	1,303
Employer contributions	414	31
Benefits paid	(363)	(595)
Settlements	(5)	0
Expenses paid	(43)	(42)
Foreign currency exchange rate changes	4	9
Plan participants' contributions	1	2
Divestiture	(92)	0
Plan assets at end of fiscal year	8,892	9,600	$ 5,159
Funded status	(1,745)	(1,832)
Pension
Change in plan assets
Plan assets at beginning of fiscal year		8,618
Plan assets acquired in L3Harris Merger	3,183	0
Actual return on plan assets	548	1,263
Employer contributions	406	20
Benefits paid	(342)	(569)
Settlements	(5)	0
Expenses paid	(43)	(42)
Foreign currency exchange rate changes	4	9
Plan participants' contributions	1	2
Divestiture	(92)	0
Plan assets at end of fiscal year	8,618	9,301	4,958
Funded status	(1,650)	(1,744)
Other Benefits
Change in plan assets
Plan assets at beginning of fiscal year		274
Plan assets acquired in L3Harris Merger	68	0
Actual return on plan assets	18	40
Employer contributions	8	11
Benefits paid	(21)	(26)
Settlements	0	0
Expenses paid	0	0
Foreign currency exchange rate changes	0	0
Plan participants' contributions	0	0
Divestiture	0	0
Plan assets at end of fiscal year	274	299	$ 201
Funded status	$ (95)	$ (88)