Accumulated Other Comprehensive Loss - Changes in AOCI (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 29, 2018	Sep. 30, 2017
Accumulated other comprehensive income (loss):
Balance - beginning of period	$ (1,589.1)	$ (1,921.6)
Other comprehensive (loss) income before reclassifications	(177.5)	276.0
Reclassification adjustments to earnings	15.4	16.3
Net other comprehensive (loss) income	(162.1)	299.6
Balance - end of period	(1,751.2)	(1,622.0)
Currency translation adjustment and other1
Accumulated other comprehensive income (loss):
Balance - beginning of period	(1,108.2)	(1,586.7)
Other comprehensive (loss) income before reclassifications	(286.7)	449.7
Reclassification adjustments to earnings	0.0	0.0
Net other comprehensive (loss) income	(286.7)	454.4
Balance - end of period	(1,394.9)	(1,132.3)
Unrealized gains (losses) on cash flow hedges, net of tax
Accumulated other comprehensive income (loss):
Balance - beginning of period	(112.6)	(46.3)
Other comprehensive (loss) income before reclassifications	52.2	(69.4)
Reclassification adjustments to earnings	15.8	(1.4)
Net other comprehensive (loss) income	68.0	(70.8)
Balance - end of period	(44.6)	(117.1)
Unrealized gains (losses) on net investment hedges, net of tax
Accumulated other comprehensive income (loss):
Balance - beginning of period	3.4	88.6
Other comprehensive (loss) income before reclassifications	50.5	(85.3)
Reclassification adjustments to earnings	(8.8)	0.0
Net other comprehensive (loss) income	41.7	(85.3)
Balance - end of period	45.1	3.3
Pension gains (losses), net of tax
Accumulated other comprehensive income (loss):
Balance - beginning of period	(371.7)	(377.2)
Other comprehensive (loss) income before reclassifications	6.5	(19.0)
Reclassification adjustments to earnings	8.4	17.7
Net other comprehensive (loss) income	14.9	1.3
Balance - end of period	$ (356.8)	(375.9)
Disposal Group, Not Discontinued Operations [Member] \| Currency translation adjustment and other1
Accumulated other comprehensive income (loss):
Reclassification adjustments to earnings		(4.7)
Disposal Group, Not Discontinued Operations [Member]
Accumulated other comprehensive income (loss):
Reclassification adjustments to earnings		(7.3)
Disposal Group, Not Discontinued Operations [Member] \| Unrealized gains (losses) on cash flow hedges, net of tax
Accumulated other comprehensive income (loss):
Reclassification adjustments to earnings		0.0
Disposal Group, Not Discontinued Operations [Member] \| Unrealized gains (losses) on net investment hedges, net of tax
Accumulated other comprehensive income (loss):
Reclassification adjustments to earnings		0.0
Disposal Group, Not Discontinued Operations [Member] \| Pension gains (losses), net of tax
Accumulated other comprehensive income (loss):
Reclassification adjustments to earnings		$ 2.6

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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