Pension Plans - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jan. 03, 2015	Dec. 28, 2013	Dec. 29, 2012
Defined Benefit Plan Disclosure [Line Items]
Normal retirement age	65 years
Accumulated benefit obligation	$ 1,274.3	$ 1,101.4
Description of amortization actuarial gains and losses	Actuarial gains and losses in excess of 10 percent of the greater of the projected benefit obligation or market-related value of assets are amortized on a straight-line basis over the average remaining service period of active participants or over the average remaining life expectancy for plans with primarily inactive participants.
Expected long-term rate of return on plan assets	7.40%	7.60%	7.70%
Expense recognized related to 401(k)plan	6.5	5.9	5.7
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Time horizon for asset under risk and correlation assumption (in years)	10 years
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Time horizon for asset under risk and correlation assumption (in years)	20 years
Domestic Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted-average discount rate	4.20%
Description of discount rate assumption	Lowering Snap-on's domestic discount rate assumption by 50 basis points (100 basis points ("bps") equals 1.0 percent) would have increased Snap-on's 2014 domestic pension expense and projected benefit obligation by approximately $6.0 million and $63.4 million, respectively.
Discount rate assumption	0.50%
Increase in pension expense	6.0
Increase in projected benefit obligation	63.4
Percentage of projected benefit obligations	82.00%
Expected future employer contributions	2.0
Expected long-term rate of return on plan assets	7.60%
Foreign Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted-average discount rate	3.30%
Description of discount rate assumption	Lowering Snap-on's foreign discount rate assumption by 50 bps would have increased Snap-on's 2014 foreign pension expense and projected benefit obligation by approximately $1.9 million and $22.7 million, respectively.
Discount rate assumption	0.50%
Increase in pension expense	1.9
Increase in projected benefit obligation	22.7
Expected future employer contributions	$ 7.1