Segments - Net Sales by Segment (Detail) - USD ($) $ in Millions	3 Months Ended
Apr. 02, 2016	Apr. 04, 2015
Segment Reporting Information [Line Items]
Net sales	$ 834.2	$ 827.8
Financial services revenue	66.3	57.4
Total revenues	900.5	885.2
Operating earnings	202.4	178.2
Interest expense	(13.1)	(13.0)
Other income (expense) - net	(0.7)	(0.7)
Earnings before income taxes and equity earnings	188.6	164.5
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	968.3	948.0
Operating earnings	223.8	208.0
Operating Segments [Member] \| Commercial & Industrial Group [Member]
Segment Reporting Information [Line Items]
Net sales	287.0	297.5
Operating earnings	41.1	44.0
Operating Segments [Member] \| Snap-on Tools Group [Member]
Segment Reporting Information [Line Items]
Net sales	402.5	378.2
Operating earnings	66.7	59.8
Operating Segments [Member] \| Repair Systems & Information Group [Member]
Segment Reporting Information [Line Items]
Net sales	278.8	272.3
Operating earnings	69.0	63.9
Operating Segments [Member] \| Financial Services [Member]
Segment Reporting Information [Line Items]
Operating earnings	47.0	40.3
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	(134.1)	(120.2)
Corporate [Member]
Segment Reporting Information [Line Items]
Operating earnings	$ (21.4)	$ (29.8)

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
-SubTopic 10
-Section S99
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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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