Segment Information - Reconciliation of segment profit to income from continuing operations before income taxes (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Apr. 01, 2017
Revenues
Total revenues	$ 3,296	$ 3,093
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
Special charges	0	(37)
Income from continuing operations before income taxes	218	121
Operating Segment
Segment Profit
Segment Profit	279	219
Corporate
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
Corporate expenses and other, net	(27)	(27)
Textron Aviation
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
Special charges		(11)
Textron Systems
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
Special charges		(1)
Industrial
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
Special charges		(25)
Finance
Revenues
Financial Services Revenues	16
Finance \| Operating Segment
Segment Profit
Segment Profit	6	4
Manufacturing group \| Reconciling Items
Reconciliation of Operating Profit (Loss) from Segments to Consolidated
Interest expense, net for Manufacturing group	(34)	(34)
Manufacturing group \| Textron Aviation
Revenues
Total revenues	1,010	970
Manufacturing group \| Textron Aviation \| Operating Segment
Segment Profit
Segment Profit	72	36
Manufacturing group \| Bell
Revenues
Total revenues	752	697
Manufacturing group \| Bell \| Operating Segment
Segment Profit
Segment Profit	87	83
Manufacturing group \| Textron Systems
Revenues
Total revenues	387	416
Manufacturing group \| Textron Systems \| Operating Segment
Segment Profit
Segment Profit	50	20
Manufacturing group \| Industrial
Revenues
Total revenues	1,131	992
Manufacturing group \| Industrial \| Operating Segment
Segment Profit
Segment Profit	64	76
Finance group \| Finance
Revenues
Financial Services Revenues	$ 16	$ 18

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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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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 25
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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-Name Accounting Standards Codification
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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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