Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill by Segment (Detail) $ in Millions	3 Months Ended
Mar. 28, 2020 USD ($)
Goodwill [Roll Forward]
Balance as of December 28, 2019	$ 913.8
Currency translation	(21.3)
Acquisitions and related adjustments	5.7
Balance as of March 28, 2020	898.2
Commercial & Industrial Group
Goodwill [Roll Forward]
Balance as of December 28, 2019	286.2
Currency translation	(11.5)
Acquisitions and related adjustments	0.0
Balance as of March 28, 2020	274.7
Snap-on Tools Group
Goodwill [Roll Forward]
Balance as of December 28, 2019	12.5
Currency translation	0.0
Acquisitions and related adjustments	0.0
Balance as of March 28, 2020	12.5
Repair Systems & Information Group
Goodwill [Roll Forward]
Balance as of December 28, 2019	615.1
Currency translation	(9.8)
Acquisitions and related adjustments	5.7
Balance as of March 28, 2020	$ 611.0

Goodwill acquired and related adjustment.

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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