Special Charges - Restructuring plans and special charges (Details)	1 Months Ended	3 Months Ended			12 Months Ended
	Dec. 31, 2019 USD ($)	Jan. 04, 2020 USD ($)	Dec. 29, 2018 USD ($) position	Apr. 01, 2017 USD ($)	Jan. 04, 2020 USD ($)	Dec. 29, 2018 USD ($)	Dec. 30, 2017 USD ($)
Special Charges
Special charges		$ 72,000,000	$ 73,000,000		$ 72,000,000	$ 73,000,000	$ 130,000,000
Severance Costs
Special Charges
Special charges					46,000,000		46,000,000
Contract Terminations and Other
Special Charges
Special charges					11,000,000		26,000,000
Industrial
Special Charges
Special charges					38,000,000	73,000,000	58,000,000
Industrial | Severance Costs
Special Charges
Special charges					21,000,000	8,000,000	26,000,000
Industrial | Contract Terminations and Other
Special Charges
Special charges					11,000,000	18,000,000	19,000,000
Textron Aviation
Special Charges
Special charges					29,000,000		28,000,000
Textron Aviation | Severance Costs
Special Charges
Special charges					25,000,000		11,000,000
Corporate
Special Charges
Special charges					5,000,000
Bell
Special Charges
Special charges							23,000,000
Bell | Severance Costs
Special Charges
Special charges							3,000,000
Bell | Contract Terminations and Other
Special Charges
Special charges							8,000,000
Textron Systems
Special Charges
Special charges							21,000,000
Textron Systems | Severance Costs
Special Charges
Special charges							6,000,000
Textron Systems | Contract Terminations and Other
Special Charges
Special charges							(1,000,000)
2019 Restructuring Plan
Special Charges
Special charges	$ 72,000,000
Number of positions eliminated	1,000
2018 Restructuring Plan
Special Charges
Special charges			$ 73,000,000
Number of positions eliminated | position			400
2018 Restructuring Plan | Specialized vehicles
Special Charges
Number of positions eliminated, as a percentage of total workforce			10.00%
2018 Restructuring Plan | Severance Costs
Special Charges
Special charges			$ 8,000,000
2018 Restructuring Plan | Contract Terminations and Other
Special Charges
Special charges			18,000,000
2018 Restructuring Plan | Industrial | Specialized vehicles
Special Charges
Special charges			73,000,000
2016 Restructuring Plan
Special Charges
Special charges for additional restructuring actions							90,000,000
2017 Restructuring Plan
Special Charges
Special charges				$ 28,000,000
Arctic Cat Acquisition
Special Charges
Special charges							130,000,000
Asset Impairments
Special Charges
Special charges					10,000,000		46,000,000
Asset Impairments | Industrial
Special Charges
Special charges					6,000,000	$ 47,000,000	1,000,000
Asset Impairments | Textron Aviation
Special Charges
Special charges					4,000,000		17,000,000
Asset Impairments | Bell
Special Charges
Special charges							12,000,000
Asset Impairments | Textron Systems
Special Charges
Special charges							16,000,000
Asset Impairments | 2018 Restructuring Plan
Special Charges
Special charges			$ 47,000,000
Acquisition Integration and Transaction Costs
Special Charges
Special charges					5,000,000		12,000,000
Acquisition Integration and Transaction Costs | Industrial
Special Charges
Special charges							12,000,000
Acquisition Integration and Transaction Costs | Corporate
Special Charges
Special charges					5,000,000
Acquisition Integration and Transaction Costs | Arctic Cat Acquisition
Special Charges
Special charges							$ 12,000,000
Restructuring Costs | Kautex Business Review
Special Charges
Special charges					$ 5,000,000