Segment Information - Reconciliation of segment profit to income from continuing operations before income taxes (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Revenues
Manufacturing revenues	$ 3,466	$ 3,231	$ 10,127	$ 9,903
Finance revenues	18	20	54	60
Total revenues	3,484	3,251	10,181	9,963
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
Special charges	(25)	(115)	(75)	(115)
Income from continuing operations before income taxes	203	107	539	582
Operating Segment
Segment Profit
Segment Profit	295	310	809	918
Corporate
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
Corporate expenses and other, net	(30)	(53)	(88)	(116)
Manufacturing group \| Reconciling Items
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
Interest expense, net for Manufacturing group	(37)	(35)	(107)	(105)
Textron Aviation
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
Special charges	(6)	(35)	(28)	(35)
Textron Aviation \| Manufacturing group
Revenues
Manufacturing revenues	1,154	1,198	3,295	3,485
Textron Aviation \| Manufacturing group \| Operating Segment
Segment Profit
Segment Profit	93	100	183	254
Bell
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
Special charges		(8)		(8)
Bell \| Manufacturing group
Revenues
Manufacturing revenues	812	734	2,334	2,352
Bell \| Manufacturing group \| Operating Segment
Segment Profit
Segment Profit	106	97	301	260
Textron Systems
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
Special charges	(6)	(59)	(5)	(59)
Textron Systems \| Manufacturing group
Revenues
Manufacturing revenues	458	413	1,351	1,224
Textron Systems \| Manufacturing group \| Operating Segment
Segment Profit
Segment Profit	40	44	102	133
Industrial
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
Special charges	(13)	(13)	(42)	(13)
Industrial \| Manufacturing group
Revenues
Manufacturing revenues	1,042	886	3,147	2,842
Industrial \| Manufacturing group \| Operating Segment
Segment Profit
Segment Profit	49	66	207	256
Finance
Revenues
Finance revenues	18	20	54	60
Finance \| Operating Segment
Segment Profit
Segment Profit	$ 7	$ 3	$ 16	$ 15

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Operating profit for all operating segments before income taxes.

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Includes items that are either isolated or temporary in nature that are excluded from the Company's segment profit measure, including restructuring charges and asset impairments.

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The aggregate financial services revenue and operating interest income earned during the reporting period.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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The net amount of operating interest income (expense).

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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