Segments - Net Sales by Segment (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Segment Reporting Information [Line Items]
Net sales	$ 954.6	$ 921.4	$ 1,890.1	$ 1,808.5
Financial services revenue	82.0	77.7	165.0	154.5
Total revenues	1,036.6	999.1	2,055.1	1,963.0
Operating earnings	250.9	238.3	485.5	461.0
Interest expense	(12.0)	(13.0)	(25.6)	(25.7)
Other income (expense) – net	(0.6)	(1.9)	2.2	(4.3)
Earnings before income taxes and equity earnings	238.3	223.4	462.1	431.0
Commercial & Industrial Group
Segment Reporting Information [Line Items]
Financial services revenue	0.0		0.0
Total revenues	337.8		669.4
Snap-on Tools Group
Segment Reporting Information [Line Items]
Financial services revenue	0.0		0.0
Total revenues	411.9		816.6
Repair Systems & Information Group
Segment Reporting Information [Line Items]
Financial services revenue	0.0		0.0
Total revenues	343.1		680.1
Financial Services
Segment Reporting Information [Line Items]
Financial services revenue	82.0		165.0
Total revenues	82.0		165.0
Operating Segments
Segment Reporting Information [Line Items]
Net sales	1,092.8	1,061.9	2,166.1	2,088.8
Operating earnings	274.5	260.5	532.6	504.3
Operating Segments \| Commercial & Industrial Group
Segment Reporting Information [Line Items]
Net sales	337.8	310.0	669.4	608.7
Operating earnings	49.0	43.0	95.5	84.9
Operating Segments \| Snap-on Tools Group
Segment Reporting Information [Line Items]
Net sales	411.9	413.8	816.6	823.2
Operating earnings	79.0	80.7	147.9	151.0
Operating Segments \| Repair Systems & Information Group
Segment Reporting Information [Line Items]
Net sales	343.1	338.1	680.1	656.9
Operating earnings	88.7	82.2	174.5	161.3
Operating Segments \| Financial Services
Segment Reporting Information [Line Items]
Operating earnings	57.8	54.6	114.7	107.1
Intersegment eliminations
Segment Reporting Information [Line Items]
Net sales	(138.2)	(140.5)	(276.0)	(280.3)
Total revenues	(138.2)		(276.0)
Corporate
Segment Reporting Information [Line Items]
Operating earnings	$ (23.6)	$ (22.2)	$ (47.1)	$ (43.3)

The aggregate financial services revenue and operating interest income earned during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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