Segments - Assets by Segment (Detail) - USD ($) $ in Millions	Apr. 01, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Assets	$ 4,877.8	$ 4,723.2
Operating Segments [Member]
Segment Reporting Information [Line Items]
Assets	4,702.5	4,575.9
Operating Segments [Member] | Commercial & Industrial Group [Member]
Segment Reporting Information [Line Items]
Assets	931.1	907.1
Operating Segments [Member] | Snap-on Tools Group [Member]
Segment Reporting Information [Line Items]
Assets	687.9	668.1
Operating Segments [Member] | Repair Systems & Information Group [Member]
Segment Reporting Information [Line Items]
Assets	1,247.2	1,211.0
Operating Segments [Member] | Financial Services [Member]
Segment Reporting Information [Line Items]
Assets	1,836.3	1,789.7
Corporate [Member]
Segment Reporting Information [Line Items]
Assets	238.6	212.3
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Assets	$ (63.3)	$ (65.0)