EQUITY AND LONG-TERM INCENTIVE COMPENSATION - Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 03, 2021	Mar. 28, 2020	Dec. 31, 2020	Dec. 31, 2019
Components of accumulated other comprehensive income, net of tax [Roll Forward]
Balance at beginning of period	$ 629.2	$ 502.4
Other comprehensive income before reclassifications	3.9	(12.4)
Amounts reclassified from accumulated other comprehensive income (loss)	(1.2)	(0.5)
Current-period other comprehensive income (loss)	2.7	(12.9)
Balance at end of period	660.8	515.1
Accum. Other Comprehensive Income
Components of accumulated other comprehensive income, net of tax [Roll Forward]
Balance at beginning of period	248.5	244.3
Balance at end of period	251.2	231.4
Foreign Currency Translation Adjustment
Components of accumulated other comprehensive income, net of tax [Roll Forward]
Balance at beginning of period	238.6	228.0
Other comprehensive income before reclassifications	0.6	(5.7)
Amounts reclassified from accumulated other comprehensive income (loss)	0.0	0.0
Current-period other comprehensive income (loss)	0.6	(5.7)
Balance at end of period	239.2	222.3
Net Unrealized Losses on Qualifying Cash Flow Hedges
Components of accumulated other comprehensive income, net of tax [Roll Forward]
Balance at beginning of period	(4.4)	(1.6)
Other comprehensive income before reclassifications	3.3	(6.8)
Amounts reclassified from accumulated other comprehensive income (loss)	(0.3)	0.4
Current-period other comprehensive income (loss)	3.0	(6.4)
Balance at end of period	(1.4)	(8.0)
Tax benefit (provision)	(0.4)	(2.7)	$ (1.4)	$ (0.5)
Pension and Postretirement Liability Adjustment
Components of accumulated other comprehensive income, net of tax [Roll Forward]
Balance at beginning of period	14.3	17.9
Other comprehensive income before reclassifications	0.0	0.1
Amounts reclassified from accumulated other comprehensive income (loss)	(0.9)	(0.9)
Current-period other comprehensive income (loss)	(0.9)	(0.8)
Balance at end of period	13.4	17.1
Tax benefit (provision)	$ 4.6	$ 5.8	$ 4.9	$ 6.1