Segments - Net Sales by Segment (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 29, 2013	Jun. 30, 2012	Jun. 29, 2013	Jun. 30, 2012
Segment Reporting Information [Line Items]
Net sales	$ 764.1	$ 737.9	$ 1,505.8	$ 1,473.1
Financial services revenue	44.5	39.9	88.5	77.9
Total revenues	808.6	777.8	1,594.3	1,551.0
Operating earnings	148.4	130.2	286.7	251.6
Interest expense	(13.8)	(13.9)	(27.4)	(27.8)
Other income (expense) - net	(1.7)	0.1	(2.3)	(0.3)
Earnings before income taxes and equity earnings	132.9	116.4	257.0	223.5
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	858.6	835.8	1,698.4	1,665.0
Operating earnings	175.4	155.1	340.2	302.9
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	(94.5)	(97.9)	(192.6)	(191.9)
Corporate [Member]
Segment Reporting Information [Line Items]
Operating earnings	(27.0)	(24.9)	(53.5)	(51.3)
Commercial & Industrial Group [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	266.2	283.4	532.6	569.9
Operating earnings	33.6	32.8	64.2	62.0
Snap-on Tools Group [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	346.2	325.0	673.5	641.6
Operating earnings	54.5	44.5	101.7	90.6
Repair Systems & Information Group [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	246.2	227.4	492.3	453.5
Operating earnings	56.7	52.2	113.2	100.8
Financial Services [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating earnings	$ 30.6	$ 25.6	$ 61.1	$ 49.5

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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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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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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