Accounts Receivable and Finance Receivables - Finance receivables (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Finance Receivables
Finance receivables, gross	$ 850	$ 976
Allowance for losses	(31)	(41)	$ (48)
Total finance receivables, net	819	935
Finance receivables held for sale		$ 30
Average balance of loans	$ 1
Minimum
Finance Receivables
Contractual terms	5 years
Amortization period	8 years
Maximum
Finance Receivables
Contractual terms	10 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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Namespace Prefix:	txt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Contractual term of installment contracts and finance leases receivables.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

Name:	txt_FinanceReceivablesNet
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://www.xbrl.org/2003/role/presentationRef
-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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The face amount of loans that will be sold to other entities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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Period Type:	duration

- Details

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