Financial Guarantees (Detail) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($)
Guarantor Obligations [Line Items]
Guarantee Obligations Maximum Potential Payment	$ 246.2
Guarantee Liability Carrying Amount	25.9
Guarantees on the residual values of leased properties
Guarantor Obligations [Line Items]
Guarantee Obligations Maximum Potential Payment	101.6
Guarantee Liability Carrying Amount	$ 0.0
Guarantees on the residual values of leased properties \| Minimum [Member]
Guarantor Obligations [Line Items]
Guarantee Obligation Term	1 year
Guarantees on the residual values of leased properties \| Maximum [Member]
Guarantor Obligations [Line Items]
Guarantee Obligation Term	5 years
Standby Letters of Credit [Member]
Guarantor Obligations [Line Items]
Guarantee Obligations Maximum Potential Payment	$ 73.0
Guarantee Liability Carrying Amount	$ 0.0
Standby Letters of Credit [Member] \| Maximum [Member]
Guarantor Obligations [Line Items]
Guarantee Obligation Term	3 years
Commercial customer financing arrangements
Guarantor Obligations [Line Items]
Guarantee Obligations Maximum Potential Payment	$ 71.6
Guarantee Liability Carrying Amount	$ 25.9
Commercial customer financing arrangements \| Maximum [Member]
Guarantor Obligations [Line Items]
Guarantee Obligation Term	6 years

Guarantee Obligation Term

No definition available.

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Namespace Prefix:	swk_
Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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