Accumulated Other Comprehensive Loss - Changes in AOCI (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 30, 2019	Mar. 31, 2018
Accumulated other comprehensive income (loss):
Balance - beginning of period	$ (1,814.3)	$ (1,589.1)
Other comprehensive (loss) income before reclassifications	2.6	91.1
Reclassification adjustments to earnings	(1.6)	4.7
Net other comprehensive (loss) income	1.0	95.8
Balance - end of period	(1,813.3)	(1,493.3)
Currency translation adjustment and other
Accumulated other comprehensive income (loss):
Balance - beginning of period	(1,481.2)	(1,108.2)
Other comprehensive (loss) income before reclassifications	(18.9)	122.9
Reclassification adjustments to earnings	0.0	0.0
Net other comprehensive (loss) income	(18.9)	122.9
Balance - end of period	(1,500.1)	(985.3)
Unrealized (losses) gains on cash flow hedges, net of tax
Accumulated other comprehensive income (loss):
Balance - beginning of period	(26.8)	(112.6)
Other comprehensive (loss) income before reclassifications	(4.3)	8.3
Reclassification adjustments to earnings	2.1	4.6
Net other comprehensive (loss) income	(2.2)	12.9
Balance - end of period	(29.0)	(99.7)
Unrealized gains (losses) on net investment hedges, net of tax
Accumulated other comprehensive income (loss):
Balance - beginning of period	63.3	3.4
Other comprehensive (loss) income before reclassifications	29.2	(32.9)
Reclassification adjustments to earnings	(6.6)	(2.8)
Net other comprehensive (loss) income	22.6	(35.7)
Balance - end of period	85.9	(32.3)
Pension (losses) gains, net of tax
Accumulated other comprehensive income (loss):
Balance - beginning of period	(369.6)	(371.7)
Other comprehensive (loss) income before reclassifications	(3.4)	(7.2)
Reclassification adjustments to earnings	2.9	2.9
Net other comprehensive (loss) income	(0.5)	(4.3)
Balance - end of period	$ (370.1)	$ (376.0)