VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Inventory obsolescence expense	$ 116.0	$ 180.5
Allowance for doubtful accounts receivable
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	93.0	129.3	$ 122.9
Charged to Costs and Expenses	115.4	162.4	221.9
Charged to Revenue	0.0	0.0	0.0
Deductions	(141.8)	(198.7)	(215.5)
Balance at End of Period	66.6	93.0	129.3
Refund liability
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	12.3
Charged to Costs and Expenses	0.0
Charged to Revenue	132.6
Deductions	(134.2)
Balance at End of Period	10.7	12.3
Refund liability
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	12.3	9.3	8.2
Charged to Costs and Expenses		0.0	0.0
Charged to Revenue		172.3	197.9
Deductions		(169.3)	(196.8)
Balance at End of Period		12.3	9.3
Allowance for inventory obsolescence
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	146.1	61.3	58.4
Charged to Costs and Expenses	37.1	113.5	36.7
Charged to Revenue	0.0	0.0	0.0
Deductions	(101.2)	(28.7)	(33.8)
Balance at End of Period	82.0	146.1	61.3
Deferred tax asset valuation allowance
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	3,257.5	3,217.6	3,296.0
Charged to Costs and Expenses	(297.5)	39.9	(78.4)
Charged to Revenue	0.0	0.0	0.0
Deductions	0.0	0.0	0.0
Balance at End of Period	$ 2,960.0	3,257.5	$ 3,217.6
Inventory write-off
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Inventory obsolescence expense		$ 88.0