Segments - Net Sales by Segment (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jul. 04, 2015	Jun. 28, 2014	Jul. 04, 2015	Jun. 28, 2014
Segment Reporting Information [Line Items]
Net sales	$ 851.8	$ 826.5	$ 1,679.6	$ 1,614.0
Financial services revenue	58.7	51.7	116.1	101.9
Total revenues	910.5	878.2	1,795.7	1,715.9
Operating earnings	192.2	172.9	370.4	329.0
Interest expense	(12.9)	(12.7)	(25.9)	(26.4)
Other income (expense) - net	(0.7)	0.3	(1.4)	0.2
Earnings before income taxes and equity earnings	178.6	160.5	343.1	302.8
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	971.9	934.8	1,919.9	1,831.7
Operating earnings	219.3	198.1	427.3	378.9
Operating Segments [Member] \| Commercial & Industrial Group [Member]
Segment Reporting Information [Line Items]
Net sales	295.8	287.2	593.3	577.8
Operating earnings	42.2	38.2	86.2	77.3
Operating Segments [Member] \| Snap-on Tools Group [Member]
Segment Reporting Information [Line Items]
Net sales	398.7	369.1	776.9	712.7
Operating earnings	68.0	60.5	127.8	109.7
Operating Segments [Member] \| Repair Systems & Information Group [Member]
Segment Reporting Information [Line Items]
Net sales	277.4	278.5	549.7	541.2
Operating earnings	67.7	64.6	131.6	122.7
Operating Segments [Member] \| Financial Services [Member]
Segment Reporting Information [Line Items]
Operating earnings	41.4	34.8	81.7	69.2
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	(120.1)	(108.3)	(240.3)	(217.7)
Corporate [Member]
Segment Reporting Information [Line Items]
Operating earnings	$ (27.1)	$ (25.2)	$ (56.9)	$ (49.9)

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

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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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