Revenue Recognition - Revenue Disaggregation (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									$ 3,708.3	$ 3,719.6
Net sales									4,067.7	4,070.4	$ 4,000.3
Europe
Disaggregation of Revenue [Line Items]
Net sales									730.3	784.7	748.8
Commercial & Industrial Group
Disaggregation of Revenue [Line Items]
Net sales									1,345.7	1,343.3
Snap-on Tools Group
Disaggregation of Revenue [Line Items]
Net sales									1,612.9	1,613.8
Repair Systems  & Information Group
Disaggregation of Revenue [Line Items]
Net sales									1,334.5	1,334.4
Financial Services
Disaggregation of Revenue [Line Items]
Net sales									337.7	329.7
Intersegment eliminations
Disaggregation of Revenue [Line Items]
Net sales									(563.1)	(550.8)
Product and Service, Other
Disaggregation of Revenue [Line Items]
Revenue not from contract with customer									21.7	21.1
Product And Services, Excluding Financial Services
Disaggregation of Revenue [Line Items]
Net sales	$ 955.2	$ 901.8	$ 951.3	$ 921.7	$ 952.5	$ 898.1	$ 954.6	$ 935.5	3,730.0	3,740.7	3,686.9
Product And Services, Excluding Financial Services | Vehicle service professionals
Disaggregation of Revenue [Line Items]
Net sales									2,777.3	2,780.2
Product And Services, Excluding Financial Services | All other professionals
Disaggregation of Revenue [Line Items]
Net sales									952.7	960.5
Product And Services, Excluding Financial Services | North America
Disaggregation of Revenue [Line Items]
Net sales									2,654.6	2,592.3
Product And Services, Excluding Financial Services | Europe
Disaggregation of Revenue [Line Items]
Net sales									664.9	718.4
Product And Services, Excluding Financial Services | All other
Disaggregation of Revenue [Line Items]
Net sales									410.5	430.0
Product And Services, Excluding Financial Services | Commercial & Industrial Group
Disaggregation of Revenue [Line Items]
Net sales									1,038.2	1,051.6
Product And Services, Excluding Financial Services | Commercial & Industrial Group | Vehicle service professionals
Disaggregation of Revenue [Line Items]
Net sales									85.5	91.1
Product And Services, Excluding Financial Services | Commercial & Industrial Group | All other professionals
Disaggregation of Revenue [Line Items]
Net sales									952.7	960.5
Product And Services, Excluding Financial Services | Commercial & Industrial Group | North America
Disaggregation of Revenue [Line Items]
Net sales									482.1	466.5
Product And Services, Excluding Financial Services | Commercial & Industrial Group | Europe
Disaggregation of Revenue [Line Items]
Net sales									291.7	311.9
Product And Services, Excluding Financial Services | Commercial & Industrial Group | All other
Disaggregation of Revenue [Line Items]
Net sales									264.4	273.2
Product And Services, Excluding Financial Services | Snap-on Tools Group
Disaggregation of Revenue [Line Items]
Net sales									1,612.9	1,613.8
Product And Services, Excluding Financial Services | Snap-on Tools Group | Vehicle service professionals
Disaggregation of Revenue [Line Items]
Net sales									1,612.9	1,613.8
Product And Services, Excluding Financial Services | Snap-on Tools Group | All other professionals
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Product And Services, Excluding Financial Services | Snap-on Tools Group | North America
Disaggregation of Revenue [Line Items]
Net sales									1,406.1	1,378.7
Product And Services, Excluding Financial Services | Snap-on Tools Group | Europe
Disaggregation of Revenue [Line Items]
Net sales									131.9	151.3
Product And Services, Excluding Financial Services | Snap-on Tools Group | All other
Disaggregation of Revenue [Line Items]
Net sales									74.9	83.8
Product And Services, Excluding Financial Services | Repair Systems  & Information Group
Disaggregation of Revenue [Line Items]
Net sales									1,078.9	1,075.3
Product And Services, Excluding Financial Services | Repair Systems  & Information Group | Vehicle service professionals
Disaggregation of Revenue [Line Items]
Net sales									1,078.9	1,075.3
Product And Services, Excluding Financial Services | Repair Systems  & Information Group | All other professionals
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Product And Services, Excluding Financial Services | Repair Systems  & Information Group | North America
Disaggregation of Revenue [Line Items]
Net sales									766.4	747.1
Product And Services, Excluding Financial Services | Repair Systems  & Information Group | Europe
Disaggregation of Revenue [Line Items]
Net sales									241.3	255.2
Product And Services, Excluding Financial Services | Repair Systems  & Information Group | All other
Disaggregation of Revenue [Line Items]
Net sales									71.2	73.0
Product And Services, Excluding Financial Services | Financial Services
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Product And Services, Excluding Financial Services | Financial Services | Vehicle service professionals
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Product And Services, Excluding Financial Services | Financial Services | All other professionals
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Product And Services, Excluding Financial Services | Financial Services | North America
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Product And Services, Excluding Financial Services | Financial Services | Europe
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Product And Services, Excluding Financial Services | Financial Services | All other
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Product And Services, Excluding Financial Services | Intersegment eliminations
Disaggregation of Revenue [Line Items]
Net sales									(563.1)	(550.8)	(550.4)
Product And Services, Excluding Financial Services | Intersegment eliminations | Commercial & Industrial Group
Disaggregation of Revenue [Line Items]
Net sales									307.5	291.7
Product And Services, Excluding Financial Services | Intersegment eliminations | Snap-on Tools Group
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Product And Services, Excluding Financial Services | Intersegment eliminations | Repair Systems  & Information Group
Disaggregation of Revenue [Line Items]
Net sales									255.6	259.1
Product And Services, Excluding Financial Services | Intersegment eliminations | Financial Services
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Product And Services, Excluding Financial Services | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									4,293.1	4,291.5	4,237.3
Product And Services, Excluding Financial Services | Operating Segments | Commercial & Industrial Group
Disaggregation of Revenue [Line Items]
Net sales									1,345.7	1,343.3	1,265.0
Product And Services, Excluding Financial Services | Operating Segments | Snap-on Tools Group
Disaggregation of Revenue [Line Items]
Net sales									1,612.9	1,613.8	1,625.1
Product And Services, Excluding Financial Services | Operating Segments | Repair Systems  & Information Group
Disaggregation of Revenue [Line Items]
Net sales									1,334.5	1,334.4	1,347.2
Product And Services, Excluding Financial Services | Operating Segments | Financial Services
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Financial Service
Disaggregation of Revenue [Line Items]
Revenue not from contract with customer									337.7	329.7
Net sales	$ 83.9	$ 84.1	$ 84.1	$ 85.6	$ 82.7	$ 82.0	$ 82.0	$ 83.0	337.7	329.7	$ 313.4
Financial Service | Commercial & Industrial Group
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Financial Service | Snap-on Tools Group
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Financial Service | Repair Systems  & Information Group
Disaggregation of Revenue [Line Items]
Net sales									0.0	0.0
Financial Service | Financial Services
Disaggregation of Revenue [Line Items]
Net sales									$ 337.7	$ 329.7