SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for doubtful accounts
Changes in valuation and qualifying accounts
Balance at Beginning of Year	$ 1.0	$ 0.7	$ 0.4
Additions Charged to Costs and Expenses	2.1	1.7	0.7
Reductions	(1.2)	(1.4)	(0.4)
Balance at End of Year	1.9	1.0	0.7
Deferred tax valuation allowance
Changes in valuation and qualifying accounts
Balance at Beginning of Year	8.1	7.1	6.6
Additions Charged to Costs and Expenses	0.2	1.0	0.5
Reductions	0.0	0.0	0.0
Balance at End of Year	$ 8.3	$ 8.1	$ 7.1