Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill by Segment (Detail) $ in Millions	6 Months Ended
Jun. 29, 2019 USD ($)
Goodwill [Roll Forward]
December 29, 2018	$ 902.2
Currency translation	(3.4)
Acquisitions and related adjustments	8.2
June 29, 2019	907.0
Commercial & Industrial Group
Goodwill [Roll Forward]
December 29, 2018	286.2
Currency translation	(2.0)
Acquisitions and related adjustments	6.9
June 29, 2019	291.1
Snap-on Tools Group
Goodwill [Roll Forward]
December 29, 2018	12.5
Currency translation	0.0
Acquisitions and related adjustments	0.0
June 29, 2019	12.5
Repair Systems & Information Group
Goodwill [Roll Forward]
December 29, 2018	603.5
Currency translation	(1.4)
Acquisitions and related adjustments	1.3
June 29, 2019	$ 603.4

Goodwill acquired and related adjustment.

No definition available.

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Balance Type:	debit
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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

+ Details

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Period Type:	instant

- 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

+ Details

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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.

+ Details

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- Details

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