Segments - Net Sales by Segment (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 30, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Total revenues	$ 1,007.3	$ 1,018.5
Operating earnings	249.5	234.6
Interest expense	(12.5)	(13.6)
Other income (expense) – net	1.5	2.8
Earnings before income taxes and equity earnings	238.5	223.8
Commercial & Industrial Group
Segment Reporting Information [Line Items]
Total revenues	322.5	331.6
Snap-on Tools Group
Segment Reporting Information [Line Items]
Total revenues	410.2	404.7
Repair Systems & Information Group
Segment Reporting Information [Line Items]
Total revenues	327.9	337.0
Financial Services
Segment Reporting Information [Line Items]
Total revenues	85.6	83.0
Operating Segments
Segment Reporting Information [Line Items]
Total revenues	1,060.6	1,073.3
Operating earnings	259.4	258.1
Operating Segments \| Commercial & Industrial Group
Segment Reporting Information [Line Items]
Total revenues	322.5	331.6
Operating earnings	46.5	46.5
Operating Segments \| Snap-on Tools Group
Segment Reporting Information [Line Items]
Total revenues	410.2	404.7
Operating earnings	67.2	68.9
Operating Segments \| Repair Systems & Information Group
Segment Reporting Information [Line Items]
Total revenues	327.9	337.0
Operating earnings	83.6	85.8
Operating Segments \| Financial Services
Segment Reporting Information [Line Items]
Operating earnings	62.1	56.9
Intersegment eliminations
Segment Reporting Information [Line Items]
Total revenues	(138.9)	(137.8)
Corporate
Segment Reporting Information [Line Items]
Operating earnings	(9.9)	(23.5)
Excluding Financial Services
Segment Reporting Information [Line Items]
Total revenues	921.7	935.5
Operating earnings	187.4	177.7
Excluding Financial Services \| Commercial & Industrial Group
Segment Reporting Information [Line Items]
Total revenues	249.5	258.8
Excluding Financial Services \| Snap-on Tools Group
Segment Reporting Information [Line Items]
Total revenues	410.2	404.7
Excluding Financial Services \| Repair Systems & Information Group
Segment Reporting Information [Line Items]
Total revenues	262.0	272.0
Excluding Financial Services \| Financial Services
Segment Reporting Information [Line Items]
Total revenues	0.0	0.0
Excluding Financial Services \| Operating Segments
Segment Reporting Information [Line Items]
Total revenues	921.7	935.5
Excluding Financial Services \| Operating Segments \| Commercial & Industrial Group
Segment Reporting Information [Line Items]
Total revenues	322.5	331.6
Excluding Financial Services \| Operating Segments \| Snap-on Tools Group
Segment Reporting Information [Line Items]
Total revenues	410.2	404.7
Excluding Financial Services \| Operating Segments \| Repair Systems & Information Group
Segment Reporting Information [Line Items]
Total revenues	327.9	337.0
Excluding Financial Services \| Operating Segments \| Financial Services
Segment Reporting Information [Line Items]
Total revenues	0.0	0.0
Excluding Financial Services \| Intersegment eliminations
Segment Reporting Information [Line Items]
Total revenues	(138.9)	(137.8)
Excluding Financial Services \| Intersegment eliminations \| Commercial & Industrial Group
Segment Reporting Information [Line Items]
Total revenues	73.0	72.8
Excluding Financial Services \| Intersegment eliminations \| Snap-on Tools Group
Segment Reporting Information [Line Items]
Total revenues	0.0	0.0
Excluding Financial Services \| Intersegment eliminations \| Repair Systems & Information Group
Segment Reporting Information [Line Items]
Total revenues	65.9	65.0
Excluding Financial Services \| Intersegment eliminations \| Financial Services
Segment Reporting Information [Line Items]
Total revenues	0.0	0.0
Financial Service
Segment Reporting Information [Line Items]
Total revenues	85.6	83.0
Operating earnings	62.1	56.9
Financial Service \| Commercial & Industrial Group
Segment Reporting Information [Line Items]
Total revenues	0.0	0.0
Financial Service \| Snap-on Tools Group
Segment Reporting Information [Line Items]
Total revenues	0.0	0.0
Financial Service \| Repair Systems & Information Group
Segment Reporting Information [Line Items]
Total revenues	0.0	0.0
Financial Service \| Financial Services
Segment Reporting Information [Line Items]
Total revenues	85.6	83.0
Financial Service \| Intersegment eliminations
Segment Reporting Information [Line Items]
Total revenues	$ 0.0	$ 0.0

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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