GOODWILL - Narrative (Details) - USD ($)		3 Months Ended		6 Months Ended		9 Months Ended	12 Months Ended
	Jun. 29, 2019	Jan. 01, 2021	Jul. 03, 2020	Jan. 03, 2020	Dec. 28, 2018	Oct. 02, 2020	Jan. 01, 2021	Jan. 03, 2020	Jun. 28, 2019	Jun. 29, 2018
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment loss	$ 0					$ 480,000,000
Non-cash impairment charges of long-lived assets				$ 46,000,000	$ 0		$ 767,000,000	$ 46,000,000	$ 0	$ 0
Impairment of identifiable intangible assets				0			113,000,000		0	0
Impairment of marketable software				$ 46,000,000			767,000,000		$ 0	$ 0
Aviation Systems
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment loss						$ 475,000,000
Aviation Systems | VSE | Disposal Group, Held-for-sale, Not Discontinued Operations
Finite-Lived Intangible Assets [Line Items]
Goodwill assigned to disposal group			$ 14,000,000
Commercial Aviation Solutions
Finite-Lived Intangible Assets [Line Items]
Non-cash impairment charges of long-lived assets							257,000,000
Impairment of identifiable intangible assets		$ 113,000,000
Impairment of property, plant and equipment							103,000,000
Commercial Aviation Solutions | COVID
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment loss		$ 111,000,000					461,000,000
Goodwill impairment loss attributable to noncontrolling interests							34,000,000
Non-cash impairment charges of long-lived assets							257,000,000
Impairment of identifiable intangible assets							113,000,000
Impairment of property, plant and equipment							103,000,000
Impairment charge for ROU asset							31,000,000
Impairment of marketable software							$ 10,000,000
Aviation Systems | VSE | Disposal Group, Held-for-sale, Not Discontinued Operations
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment loss			$ 14,000,000