Special Charges - Restructuring plans and special charges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Special Charges
Special charges	$ 0	$ 25	$ 0	$ 75
Severance Costs
Special Charges
Special charges		8		33
Contract Terminations and Other
Special Charges
Special charges		11		11
Industrial
Special Charges
Special charges		13		42
Industrial | Severance Costs
Special Charges
Special charges		1		20
Industrial | Contract Terminations and Other
Special Charges
Special charges		9		15
Textron Aviation
Special Charges
Special charges		6		28
Textron Aviation | Severance Costs
Special Charges
Special charges		6		11
Textron Systems
Special Charges
Special charges		6		5
Textron Systems | Severance Costs
Special Charges
Special charges		1		2
Textron Systems | Contract Terminations and Other
Special Charges
Special charges		2		(4)
Asset Impairments
Special Charges
Special charges		4		25
Asset Impairments | Industrial
Special Charges
Special charges		1		1
Asset Impairments | Textron Aviation
Special Charges
Special charges				17
Asset Impairments | Textron Systems
Special Charges
Special charges		3		7
Acquisition Transaction Costs
Special Charges
Special charges		2		6
Acquisition Transaction Costs | Industrial
Special Charges
Special charges		$ 2		$ 6