Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill by Segment (Detail) $ in Millions	9 Months Ended
Oct. 03, 2015 USD ($)
Goodwill [Line Items]
Beginning Balance	$ 810.7
Currency translation	(23.1)
Acquisition	11.1
Ending Balance	798.7
Commercial & Industrial Group [Member]
Goodwill [Line Items]
Beginning Balance	275.9
Currency translation	(20.0)
Ending Balance	255.9
Snap-on Tools Group [Member]
Goodwill [Line Items]
Beginning Balance	$ 12.5
Currency translation
Acquisition
Ending Balance	$ 12.5
Repair Systems & Information Group [Member]
Goodwill [Line Items]
Beginning Balance	522.3
Currency translation	(3.1)
Acquisition	11.1
Ending Balance	$ 530.3

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

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