Income Taxes (Schedule of Components of Provision for Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current tax expense (benefit)	$ 336.9	$ 425.1	$ 197.6
Deferred tax expense (benefit)	16.8	(143.8)	(117.4)
Benefit (provision) for income taxes	(353.7)	(281.3)	(80.2)
United States [Member]
Current tax expense (benefit)	203.4	231.9	102.2
Deferred tax expense (benefit)	35.7	(83.2)	(234.7)
Benefit (provision) for income taxes	(239.1)	(148.7)	132.5
Non-U.S. [Member]
Current tax expense (benefit)	133.5	193.2	95.4
Deferred tax expense (benefit)	(18.9)	(60.6)	117.3
Benefit (provision) for income taxes	$ (114.6)	$ (132.6)	$ (212.7)