Segments - Net Sales by Segment (Detail) - USD ($) $ in Millions	3 Months Ended
Apr. 01, 2017	Apr. 02, 2016
Segment Reporting Information [Line Items]
Net sales	$ 887.1	$ 834.2
Financial services revenue	76.8	66.3
Total revenues	963.9	900.5
Operating earnings	222.0	202.4
Interest expense	(12.7)	(13.1)
Other income (expense) - net	(1.7)	(0.7)
Earnings before income taxes and equity earnings	207.6	188.6
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	1,026.9	968.3
Operating earnings	243.1	223.8
Operating Segments [Member] \| Commercial & Industrial Group [Member]
Segment Reporting Information [Line Items]
Net sales	298.7	287.0
Operating earnings	41.6	41.1
Operating Segments [Member] \| Snap-on Tools Group [Member]
Segment Reporting Information [Line Items]
Net sales	409.4	402.5
Operating earnings	70.3	66.7
Operating Segments [Member] \| Repair Systems & Information Group [Member]
Segment Reporting Information [Line Items]
Net sales	318.8	278.8
Operating earnings	78.7	69.0
Operating Segments [Member] \| Financial Services [Member]
Segment Reporting Information [Line Items]
Operating earnings	52.5	47.0
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	(139.8)	(134.1)
Corporate [Member]
Segment Reporting Information [Line Items]
Operating earnings	$ (21.1)	$ (21.4)

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
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-Section S99
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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