Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 131.0	$ 119.6	$ (4,012.8)
Other comprehensive income (loss):
Foreign currency translation adjustments	(156.1)	328.5	(63.3)
Change in fair value of derivative financial instruments	(5.7)	9.7	(5.3)
Change in fair value of investment securities	0.0	(14.1)	8.7
Change in post-retirement and pension liability	(5.7)	10.8	(6.6)
Other comprehensive income (loss), net of tax	(167.5)	334.9	(66.5)
Comprehensive income (loss)	$ (36.5)	$ 454.5	$ (4,079.3)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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