Consolidated Statements of Earnings - USD ($) shares in Millions, $ in Millions	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Income Statement [Abstract]
Net sales	$ 3,686.9	$ 3,430.4	$ 3,352.8
Cost of goods sold	(1,862.0)	(1,720.8)	(1,704.5)
Gross profit	1,824.9	1,709.6	1,648.3
Operating expenses	(1,160.9)	(1,054.1)	(1,053.7)
Operating earnings before financial services	664.0	655.5	594.6
Financial services revenue	313.4	281.4	240.3
Financial services expenses	(95.9)	(82.7)	(70.1)
Operating earnings from financial services	217.5	198.7	170.2
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
Income tax expense	(250.9)	(244.3)	(221.2)
Earnings before equity earnings	571.0	557.1	489.3
Equity earnings, net of tax	1.2	2.5	1.3
Net earnings	572.2	559.6	490.6
Net earnings attributable to noncontrolling interests	(14.5)	(13.2)	(11.9)
Net earnings attributable to Snap-on Incorporated	$ 557.7	$ 546.4	$ 478.7
Net earnings per share attributable to Snap-on Incorporated:
Basic	$ 9.72	$ 9.40	$ 8.24
Diluted	$ 9.52	$ 9.20	$ 8.10
Weighted-average shares outstanding:
Basic	57.4	58.1	58.1
Effect of dilutive securities	1.2	1.3	1.0
Diluted	58.6	59.4	59.1

Earnings before equity earnings.

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Operating earnings before financial services.

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Operating earnings from segment.

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The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The aggregate costs incurred during the reporting period related to financial services rendered by an entity.

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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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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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