Selected Balance Sheet Data Accounts Receivable, Net (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Accounts receivable, net
Accounts receivable	$ 98.6	$ 96.3
Less allowance for bad debts	(5.3)	(5.6)
Accounts receivable, net	$ 93.3	$ 90.7

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant