SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 410.9	$ 315.1	$ 230.4
Charged to Costs and Expenses	(158.4)	(1.1)	(231.5)
Charged to Other Accounts	(12.3)	8.1	23.8
Deductions	202.6	88.8	292.4
Balance at End of Period	442.8	410.9	315.1
Trade accounts receivable
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	9.1	7.8	7.5
Charged to Costs and Expenses	5.6	5.0	2.2
Charged to Other Accounts	0.0	0.0	0.0
Deductions	(3.8)	(3.7)	(1.9)
Balance at End of Period	10.9	9.1	7.8
Deferred income tax asset valuation allowance
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	401.8	307.3	222.9
Charged to Costs and Expenses	(164.0)	(6.1)	(233.7)
Charged to Other Accounts	(12.3)	8.1	23.8
Deductions	206.4	92.5	294.3
Balance at End of Period	$ 431.9	$ 401.8	$ 307.3