Special Charges - Special Charges by Segment (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended			15 Months Ended
	Jun. 28, 2025	Jan. 03, 2026	Dec. 28, 2024	Dec. 30, 2023	Dec. 28, 2024
Special Charges [Line Items]
Restructuring charges		$ 8	$ 81
Special charges		4	78	$ 126
Severance Costs
Special Charges [Line Items]
Restructuring charges		5	49
Contract Termination and Other Costs
Special Charges [Line Items]
Restructuring charges		3	32
Textron Systems \| Restructuring Actions
Special Charges [Line Items]
Asset Impairments		0
Other		0
Special charges	$ 8	8
Textron Systems \| Severance Costs \| Restructuring Actions
Special Charges [Line Items]
Restructuring charges		5
Textron Systems \| Contract Termination and Other Costs \| Restructuring Actions
Special Charges [Line Items]
Restructuring charges	$ 3	3
2023 Restructuring Plan
Special Charges [Line Items]
Asset Impairments		0	3	87
Other		(4)	0	0
Special charges		4	78	126	$ 204
2023 Restructuring Plan \| Severance Costs
Special Charges [Line Items]
Restructuring charges		5	43	39
2023 Restructuring Plan \| Contract Termination and Other Costs
Special Charges [Line Items]
Restructuring charges		3	32	0	32
2023 Restructuring Plan \| Industrial
Special Charges [Line Items]
Asset Impairments		0	3	87	$ 90
Other		(4)	0	0
Special charges		(4)	72	108
2023 Restructuring Plan \| Industrial \| Severance Costs
Special Charges [Line Items]
Restructuring charges		0	37	21
2023 Restructuring Plan \| Industrial \| Contract Termination and Other Costs
Special Charges [Line Items]
Restructuring charges		$ 0	32	0
2023 Restructuring Plan \| Bell
Special Charges [Line Items]
Asset Impairments			0	0
Other			0	0
Special charges			1	13
2023 Restructuring Plan \| Bell \| Severance Costs
Special Charges [Line Items]
Restructuring charges			1	13
2023 Restructuring Plan \| Bell \| Contract Termination and Other Costs
Special Charges [Line Items]
Restructuring charges			0	0
2023 Restructuring Plan \| Textron Systems
Special Charges [Line Items]
Asset Impairments			0	0
Other			0	0
Special charges			5	5
2023 Restructuring Plan \| Textron Systems \| Severance Costs
Special Charges [Line Items]
Restructuring charges			5	5
2023 Restructuring Plan \| Textron Systems \| Contract Termination and Other Costs
Special Charges [Line Items]
Restructuring charges			$ 0	$ 0