Segment and Geographic Data - Assets, capital expenditures and depreciation and amortization by segment (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Other Information by Segment
Assets	$ 14,264	$ 15,340
Capital Expenditures	369	423	$ 446
Depreciation and Amortization	437	447	449
Manufacturing group
Other Information by Segment
Assets	13,247	14,171
Capital Expenditures	369	423	446
Depreciation and Amortization	429	435	437
Operating Segment \| Finance
Other Information by Segment
Assets	1,017	1,169
Depreciation and Amortization	8	12	12
Operating Segment \| Manufacturing group \| Textron Aviation
Other Information by Segment
Assets	4,290	4,403
Capital Expenditures	132	128	157
Depreciation and Amortization	145	139	140
Operating Segment \| Manufacturing group \| Bell
Other Information by Segment
Assets	2,652	2,660
Capital Expenditures	65	73	86
Depreciation and Amortization	108	117	132
Operating Segment \| Manufacturing group \| Textron Systems
Other Information by Segment
Assets	2,254	2,330
Capital Expenditures	39	60	71
Depreciation and Amortization	54	65	75
Operating Segment \| Manufacturing group \| Industrial
Other Information by Segment
Assets	2,815	3,360
Capital Expenditures	132	158	121
Depreciation and Amortization	112	105	81
Corporate
Other Information by Segment
Assets	1,236	1,418
Capital Expenditures	1	4	11
Depreciation and Amortization	$ 10	$ 9	$ 9

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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