Segment Information - Revenue by segment and reconciliation of segment profit to income before income taxes (Details) - USD ($) $ in Millions	3 Months Ended
Apr. 04, 2020	Mar. 30, 2019
Revenues
Total revenues	$ 2,777	$ 3,109
Reconciliation of segment profit to income from continuing operations before income taxes
Special charges	(39)
Income before income taxes	69	212
Operating Segment
Segment Profit
Segment Profit	156	294
Corporate
Reconciliation of segment profit to income from continuing operations before income taxes
Corporate expenses and other, net	(14)	(47)
Finance
Revenues
Finance revenues	14	17
Finance \| Operating Segment
Segment Profit
Segment Profit	3	6
Manufacturing group
Reconciliation of segment profit to income from continuing operations before income taxes
Special charges	(39)
Manufacturing group \| Reconciling Items
Reconciliation of segment profit to income from continuing operations before income taxes
Interest expense, net for Manufacturing group	(34)	(35)
Manufacturing group \| Textron Aviation
Revenues
Total revenues	872	1,134
Manufacturing group \| Textron Aviation \| Operating Segment
Segment Profit
Segment Profit	3	106
Manufacturing group \| Bell
Revenues
Total revenues	823	739
Manufacturing group \| Bell \| Operating Segment
Segment Profit
Segment Profit	115	104
Manufacturing group \| Textron Systems
Revenues
Total revenues	328	307
Manufacturing group \| Textron Systems \| Operating Segment
Segment Profit
Segment Profit	26	28
Manufacturing group \| Industrial
Revenues
Total revenues	740	912
Manufacturing group \| Industrial \| Operating Segment
Segment Profit
Segment Profit	9	50
Finance group \| Finance
Revenues
Finance revenues	$ 14	$ 17

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