Segments - Net Sales by Segment (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 27, 2014	Sep. 28, 2013	Sep. 27, 2014	Sep. 28, 2013
Segment Reporting Information [Line Items]
Net sales	$ 806.3	$ 753.2	$ 2,420.3	$ 2,259.0
Financial services revenue	53.6	45.1	155.5	133.6
Total revenues	859.9	798.3	2,575.8	2,392.6
Operating earnings	168.3	142.9	497.3	429.6
Interest expense	(12.7)	(14.4)	(39.1)	(41.8)
Other income (expense) - net	(0.9)	(0.8)	(0.7)	(3.1)
Earnings before income taxes and equity earnings	154.7	127.7	457.5	384.7
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	925.0	861.7	2,756.7	2,560.1
Operating earnings	191.3	167.4	570.2	507.6
Operating Segments [Member] \| Commercial & Industrial Group [Member]
Segment Reporting Information [Line Items]
Net sales	298.8	275.2	876.6	807.8
Operating earnings	40.8	36.0	118.1	100.2
Operating Segments [Member] \| Snap-on Tools Group [Member]
Segment Reporting Information [Line Items]
Net sales	355.0	333.8	1,067.7	1,007.3
Operating earnings	49.5	41.9	159.2	143.6
Operating Segments [Member] \| Repair Systems & Information Group [Member]
Segment Reporting Information [Line Items]
Net sales	271.2	252.7	812.4	745.0
Operating earnings	63.3	57.9	186.0	171.1
Operating Segments [Member] \| Financial Services [Member]
Segment Reporting Information [Line Items]
Operating earnings	37.7	31.6	106.9	92.7
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	(118.7)	(108.5)	(336.4)	(301.1)
Corporate [Member]
Segment Reporting Information [Line Items]
Operating earnings	$ (23.0)	$ (24.5)	$ (72.9)	$ (78.0)

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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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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