Segments - Net Sales by Segment (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 28, 2014	Jun. 29, 2013	Jun. 28, 2014	Jun. 29, 2013
Segment Reporting Information [Line Items]
Net sales	$ 826.5	$ 764.1	$ 1,614.0	$ 1,505.8
Financial services revenue	51.7	44.5	101.9	88.5
Total revenues	878.2	808.6	1,715.9	1,594.3
Operating earnings	172.9	148.4	329.0	286.7
Interest expense	(12.7)	(13.8)	(26.4)	(27.4)
Other income (expense) - net	0.3	(1.7)	0.2	(2.3)
Earnings before income taxes and equity earnings	160.5	132.9	302.8	257.0
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	934.8	858.6	1,831.7	1,698.4
Operating earnings	198.1	175.4	378.9	340.2
Operating Segments [Member] \| Commercial & Industrial Group [Member]
Segment Reporting Information [Line Items]
Net sales	287.2	266.2	577.8	532.6
Operating earnings	38.2	33.6	77.3	64.2
Operating Segments [Member] \| Snap-on Tools Group [Member]
Segment Reporting Information [Line Items]
Net sales	369.1	346.2	712.7	673.5
Operating earnings	60.5	54.5	109.7	101.7
Operating Segments [Member] \| Repair Systems & Information Group [Member]
Segment Reporting Information [Line Items]
Net sales	278.5	246.2	541.2	492.3
Operating earnings	64.6	56.7	122.7	113.2
Operating Segments [Member] \| Financial Services [Member]
Segment Reporting Information [Line Items]
Operating earnings	34.8	30.6	69.2	61.1
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	(108.3)	(94.5)	(217.7)	(192.6)
Corporate [Member]
Segment Reporting Information [Line Items]
Operating earnings	$ (25.2)	$ (27.0)	$ (49.9)	$ (53.5)

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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-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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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

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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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