Accumulated Other Comprehensive Income (Loss) ("AOCI") Table 1 (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018 USD ($)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
As of December 31, 2017	$ (860.0)
As of September 30, 2018	(996.4)
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
As of December 31, 2017	(314.6)
Foreign currency translation adjustments	(212.6)
Unrealized gain (loss) on derivative instruments	0.0
Reclassification of derivative (gain) loss to income	0.0
Amortization of net prior service (benefit) cost and net actuarial (gain) loss to income	0.0
Ownership share of unconsolidated subsidiaries' other comprehensive income (loss)	0.0
Tax benefit (expense)	(9.9)
As of September 30, 2018	(537.1)
Gain (loss) on derivative and non-derivative instruments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
As of December 31, 2017	(110.9)
Foreign currency translation adjustments	81.6
Unrealized gain (loss) on derivative instruments	26.7
Reclassification of derivative (gain) loss to income	2.7
Amortization of net prior service (benefit) cost and net actuarial (gain) loss to income	0.0
Ownership share of unconsolidated subsidiaries' other comprehensive income (loss)	0.0
Tax benefit (expense)	(28.1)
As of September 30, 2018	(28.0)
Pension and postretirement benefit adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
As of December 31, 2017	(375.0)
Foreign currency translation adjustments	(1.0)
Unrealized gain (loss) on derivative instruments	0.0
Reclassification of derivative (gain) loss to income	0.0
Amortization of net prior service (benefit) cost and net actuarial (gain) loss to income	5.0
Ownership share of unconsolidated subsidiaries' other comprehensive income (loss)	0.0
Tax benefit (expense)	(0.9)
As of September 30, 2018	(371.9)
Equity method investments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
As of December 31, 2017	(59.5)
Foreign currency translation adjustments	0.0
Unrealized gain (loss) on derivative instruments	0.0
Reclassification of derivative (gain) loss to income	0.0
Amortization of net prior service (benefit) cost and net actuarial (gain) loss to income	0.0
Ownership share of unconsolidated subsidiaries' other comprehensive income (loss)	0.2
Tax benefit (expense)	(0.1)
As of September 30, 2018	(59.4)
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
As of December 31, 2017	(860.0)
Foreign currency translation adjustments	(132.0)
Unrealized gain (loss) on derivative instruments	26.7
Reclassification of derivative (gain) loss to income	2.7
Amortization of net prior service (benefit) cost and net actuarial (gain) loss to income	5.0
Ownership share of unconsolidated subsidiaries' other comprehensive income (loss)	0.2
Tax benefit (expense)	(39.0)
As of September 30, 2018	$ (996.4)