SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for sales returns and doubtful accounts [Roll Forward]
Reserves related to notes receivable and tax refund receivables	$ 5.6	$ 5.6	$ 5.6
Reserves related to non trade receivables		0.4
Allowance for doubtful accounts
Allowance for sales returns and doubtful accounts [Roll Forward]
Balance at Beginning of Period	1.1	9.1	6.3
Charged to Expenses	0.7	1.0	3.1
Write-offs	(0.8)	(9.0)	(0.3)
Other	0.0	0.0	0.0
Balance at End of Period	1.0	1.1	9.1
Allowance for sales returns (4)
Allowance for sales returns and doubtful accounts [Roll Forward]
Balance at Beginning of Period	1.4	1.4	3.2
Charged to Expenses		1.4	1.4
Write-offs		0.0	0.0
Other		(1.4)	(3.2)
Balance at End of Period		1.4	1.4
Allowance for inventory returns (5)
Allowance for sales returns and doubtful accounts [Roll Forward]
Balance at Beginning of Period	(0.5)	(0.6)	(2.4)
Charged to Expenses		(0.5)	(0.6)
Write-offs		0.0	0.0
Other		0.6	2.4
Balance at End of Period		(0.5)	(0.6)
Allowance for deferred tax assets
Allowance for sales returns and doubtful accounts [Roll Forward]
Balance at Beginning of Period	18.3	69.0	64.0
Charged to Expenses	(0.3)	(28.6)	5.3
Write-offs	0.0	(2.9)	(1.9)
Other	0.3	(19.2)	1.6
Balance at End of Period	$ 18.3	$ 18.3	$ 69.0