Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 01, 2021	Jul. 02, 2020	Jul. 01, 2021	Jul. 02, 2020
Statement of Comprehensive Income [Abstract]
Net loss	$ (135.3)	$ (255.9)	$ (306.9)	$ (418.9)
Foreign currency translation adjustments	(2.5)	2.9	3.9	(32.9)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	1.1	66.4	(3.8)	(26.8)
Unrealized foreign exchange gain (loss) on intercompany loan, net of tax effect of $0.1 and ($0.1) for the three months ended, respectively, and ($0.1) and $0.8 for the six months ended, respectively	(0.2)	0.3	0.3	(2.6)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax	(0.5)	(1.0)	0.7	(10.9)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax	0.0	1.0	0.9	1.1
Total other comprehensive (loss) gain	(2.1)	69.6	2.0	(72.1)
Total comprehensive loss	$ (137.4)	$ (186.3)	$ (304.9)	$ (491.0)