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

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of income (expense) related to nonoperating activities, classified as other.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Segments - Net Sales by Segment (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 30, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Apr. 02, 2016	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Segment Reporting Information [Line Items]
Net sales	$ 974.6	$ 903.8	$ 921.4	$ 887.1	$ 889.8	$ 834.1	$ 872.3	$ 834.2	$ 3,686.9	$ 3,430.4	$ 3,352.8
Financial services revenue	$ 79.9	$ 79.0	$ 77.7	$ 76.8	$ 74.2	$ 71.6	$ 69.3	$ 66.3	313.4	281.4	240.3
Total revenues									4,000.3	3,711.8	3,593.1
Operating earnings									881.5	854.2	764.8
Interest expense									(52.4)	(52.2)	(51.9)
Other income (expense) - net									(7.2)	(0.6)	(2.4)
Earnings before income taxes and equity earnings									821.9	801.4	710.5
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									4,237.3	3,962.1	3,845.5
Operating earnings									1,011.1	945.6	869.0
Operating Segments [Member] \| Commercial & Industrial Group [Member]
Segment Reporting Information [Line Items]
Net sales									1,265.0	1,148.3	1,163.6
Operating earnings									185.3	168.0	169.4
Operating Segments [Member] \| Snap-on Tools Group [Member]
Segment Reporting Information [Line Items]
Net sales									1,625.1	1,633.9	1,568.7
Operating earnings									274.5	281.1	256.0
Operating Segments [Member] \| Repair Systems & Information Group [Member]
Segment Reporting Information [Line Items]
Net sales									1,347.2	1,179.9	1,113.2
Operating earnings									333.8	297.8	273.4
Operating Segments [Member] \| Financial Services [Member]
Segment Reporting Information [Line Items]
Operating earnings									217.5	198.7	170.2
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales									(550.4)	(531.7)	(492.7)
Corporate [Member]
Segment Reporting Information [Line Items]
Operating earnings									$ (129.6)	$ (91.4)	$ (104.2)