Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill by Segment (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Apr. 04, 2015
Goodwill [Line Items]
Beginning Balance	$ 810.7
Currency translation	(32.4)
Ending Balance	778.3
Commercial & Industrial Group [Member]
Goodwill [Line Items]
Beginning Balance	275.9
Currency translation	(28.0)
Ending Balance	247.9
Snap-on Tools Group [Member]
Goodwill [Line Items]
Beginning Balance	12.5
Currency translation
Ending Balance	12.5
Repair Systems & Information Group [Member]
Goodwill [Line Items]
Beginning Balance	522.3
Currency translation	(4.4)
Ending Balance	$ 517.9