CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Statement of Comprehensive Income [Abstract]
Net Income	$ 50.8	$ 52.7	$ 205.0	$ 179.3
Other Comprehensive Income (Loss) Net of Tax:
Foreign Currency Translation Adjustments, Net of $0.0 Million Tax Effects for the Three and Nine Months Ended September 28, 2019 and $1.8 Million for the Three and Nine Months Ended September 29, 2018	(38.5)	(18.8)	(31.7)	(57.0)
Reclassification of Foreign Currency Translation Adjustments included in Net Income, Net of $0.0 Million Tax Effects for the Three and Nine Months Ended September 28, 2019	0.0	0.0	1.6	0.0
Hedging Activities:
Increase (Decrease) in Fair Value of Hedging Activities, Net of Tax Effects of $(1.6) Million and $0.9 Million for the Three Months Ended September 28, 2019 and September 29, 2018 and $1.4 Million and $0.7 Million for the Nine Months Ended September 28, 2019 and September 29, 2018, Respectively	(4.9)	3.1	4.4	2.3
Reclassification of Gains included in Net Income, Net of Tax Effects of $(1.0) Million and $(0.3) Million for the Three Months Ended September 28, 2019 and September 29, 2018 and $(1.0) Million and $(3.7) Million for the Nine Months Ended September 28, 2019 and September 29, 2018, Respectively	(3.2)	(1.0)	(3.2)	(11.3)
Pension and Post Retirement Plans:
Reclassification Adjustments for Pension and Post Retirement Benefits included in Net Income, Net of Tax Effects of $0.1 Million and $0.3 Million for the Three Months Ended September 28, 2019 and September 29, 2018 and $0.3 Million and $0.7 Million for the Nine Months Ended September 28, 2019 and September 29, 2018, Respectively	0.4	0.7	1.3	2.2
Other Comprehensive Income (Loss)	(46.2)	(16.0)	(27.6)	(63.8)
Comprehensive Income (Loss)	4.6	36.7	177.4	115.5
Less: Comprehensive Income (Loss) Attributable to Noncontrolling Interests	(0.1)	0.3	1.6	1.8
Comprehensive Income (Loss) Attributable to Regal Beloit Corporation	$ 4.7	$ 36.4	$ 175.8	$ 113.7

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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