Segments - Net Sales by Segment (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jul. 02, 2016	Jul. 04, 2015	Jul. 02, 2016	Jul. 04, 2015
Segment Reporting Information [Line Items]
Net sales	$ 872.3	$ 851.8	$ 1,706.5	$ 1,679.6
Financial services revenue	69.3	58.7	135.6	116.1
Total revenues	941.6	910.5	1,842.1	1,795.7
Operating earnings	215.9	192.2	418.3	370.4
Interest expense	(12.9)	(12.9)	(26.0)	(25.9)
Other income (expense) - net	1.2	(0.7)	0.5	(1.4)
Earnings before income taxes and equity earnings	204.2	178.6	392.8	343.1
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	997.6	971.9	1,965.9	1,919.9
Operating earnings	239.6	219.3	463.4	427.3
Operating Segments [Member] \| Commercial & Industrial Group [Member]
Segment Reporting Information [Line Items]
Net sales	285.7	295.8	572.7	593.3
Operating earnings	39.3	42.2	80.4	86.2
Operating Segments [Member] \| Snap-on Tools Group [Member]
Segment Reporting Information [Line Items]
Net sales	416.7	398.7	819.2	776.9
Operating earnings	76.3	68.0	143.0	127.8
Operating Segments [Member] \| Repair Systems & Information Group [Member]
Segment Reporting Information [Line Items]
Net sales	295.2	277.4	574.0	549.7
Operating earnings	74.5	67.7	143.5	131.6
Operating Segments [Member] \| Financial Services [Member]
Segment Reporting Information [Line Items]
Operating earnings	49.5	41.4	96.5	81.7
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	(125.3)	(120.1)	(259.4)	(240.3)
Corporate [Member]
Segment Reporting Information [Line Items]
Operating earnings	$ (23.7)	$ (27.1)	$ (45.1)	$ (56.9)

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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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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