Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill by Segment (Detail) - USD ($) $ in Millions	12 Months Ended
Jan. 02, 2021	Dec. 28, 2019
Goodwill [Roll Forward]
Beginning Balance	$ 913.8	$ 902.2
Currency translation	41.6	(7.5)
Acquisitions	27.0	19.1
Ending Balance	982.4	913.8
Commercial & Industrial Group
Goodwill [Roll Forward]
Beginning Balance	286.2	286.2
Currency translation	26.7	(6.4)
Acquisitions	18.3	6.4
Ending Balance	331.2	286.2
Snap-on Tools Group
Goodwill [Roll Forward]
Beginning Balance	12.5	12.5
Currency translation	(0.1)	0.0
Acquisitions	0.0	0.0
Ending Balance	12.4	12.5
Repair Systems & Information Group
Goodwill [Roll Forward]
Beginning Balance	615.1	603.5
Currency translation	15.0	(1.1)
Acquisitions	8.7	12.7
Ending Balance	$ 638.8	$ 615.1

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.

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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.

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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.

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