Segments - Assets by Segment (Detail) - USD ($) $ in Millions	Jul. 01, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Assets	$ 5,067.1	$ 4,723.2
Operating Segments [Member]
Segment Reporting Information [Line Items]
Assets	4,926.0	4,575.9
Operating Segments [Member] | Commercial & Industrial Group [Member]
Segment Reporting Information [Line Items]
Assets	1,052.2	907.1
Operating Segments [Member] | Snap-on Tools Group [Member]
Segment Reporting Information [Line Items]
Assets	700.8	668.1
Operating Segments [Member] | Repair Systems & Information Group [Member]
Segment Reporting Information [Line Items]
Assets	1,286.4	1,211.0
Operating Segments [Member] | Financial Services [Member]
Segment Reporting Information [Line Items]
Assets	1,886.6	1,789.7
Corporate [Member]
Segment Reporting Information [Line Items]
Assets	213.6	212.3
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Assets	$ (72.5)	$ (65.0)