Accounts Receivable and Finance Receivables - Finance receivables (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017
Finance Receivables
Finance receivables, gross	$ 789	$ 850
Allowance for losses	(29)	(31)
Total finance receivables, net	760	$ 819
Average balance of loans	$ 1
Minimum
Finance Receivables
Contractual terms	5 years
Amortization period	8 years
Maximum
Finance Receivables
Contractual terms	12 years
Amortization period	15 years

Amortization periods of installment contracts and finance leases receivables.

No definition available.

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- Definition

Average balance of installment contracts and finance leases receivables.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The carrying amount of finance receivables held for investment or sale.

+ References

No definition available.

+ Details

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- Definition

The carrying amount of financing receivables, net of the allowance for losses.

+ References

No definition available.

+ Details

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Namespace Prefix:	txt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period between issuance and maturity of loan held for sale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

+ Details

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Balance Type:	na
Period Type:	instant

- References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

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