CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Jan. 02, 2021	Dec. 28, 2019	Dec. 29, 2018
Statement of Comprehensive Income [Abstract]
Net Income	$ 193.8	$ 242.6	$ 235.8
Translation:
Foreign Currency Translation Adjustments	60.7	(9.2)	(71.2)
Reclassification of Foreign Currency Translation Adjustments Included in Net Income, Net of $— Million Tax Effects in 2020, 2019 and 2018	0.0	1.6	0.0
Hedging Activities:
Increase (Decrease) in Fair Value of Hedging Activities, Net of Tax Effects of $2.8 Million in 2020, $4.6 Million in 2019 and $(1.2) Million in 2018	8.6	14.7	(4.0)
Reclassification of Losses (Gains) Included in Net Income, Net of Tax Effects of $2.2 Million in 2020, $(0.4) Million in 2019 and $(3.8) Million in 2018	6.9	(1.3)	(12.0)
Hedging Activities	15.5	13.4	(16.0)
Pension and Post Retirement Plans:
(Increase) Decrease in Prior Service Cost and Unrecognized Gain (Loss), Net of Tax Effects of $(0.1) Million in 2020, $1.8 Million in 2019 and $(0.6) Million in 2018	(0.6)	5.7	(1.9)
Amortization of Prior Service Cost and Unrecognized Loss Included in Net Periodic Pension Cost, Net of Tax Effects of $0.2 Million in 2020, $0.5 Million in 2019 and $0.8 Million in 2018	0.5	1.5	2.9
Amortization of Prior Service Cost and Unrecognized Loss Included in Net Periodic Pension Cost, Net of Tax Effects of $0.2 Million in 2020, $0.5 Million in 2019 and $0.8 Million in 2018	(0.1)	7.2	1.0
Other Comprehensive Income (Loss)	76.1	13.0	(86.2)
Comprehensive Income	269.9	255.6	149.6
Less: Comprehensive Income Attributable to Noncontrolling Interest	6.1	3.1	2.8
Comprehensive Income Attributable to Regal Beloit Corporation	$ 263.8	$ 252.5	$ 146.8