Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill by Segment (Detail) - USD ($) $ in Millions	12 Months Ended
Jan. 01, 2022	Jan. 02, 2021
Goodwill [Roll Forward]
Beginning Balance	$ 982.4	$ 913.8
Currency translation	(30.7)	41.6
Acquisitions	164.8	27.0
Ending Balance	1,116.5	982.4
Commercial & Industrial Group
Goodwill [Roll Forward]
Beginning Balance	331.2	286.2
Currency translation	(19.4)	26.7
Acquisitions	14.0	18.3
Ending Balance	325.8	331.2
Snap-on Tools Group
Goodwill [Roll Forward]
Beginning Balance	12.4	12.5
Currency translation	0.0	(0.1)
Acquisitions	0.0	0.0
Ending Balance	12.4	12.4
Repair Systems & Information Group
Goodwill [Roll Forward]
Beginning Balance	638.8	615.1
Currency translation	(11.3)	15.0
Acquisitions	150.8	8.7
Ending Balance	$ 778.3	$ 638.8

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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