Other Financial Information - Inventories, Net (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Schedule Of Inventory [Line Items]
Production and service materials	$ 72.6	$ 60.6
Finished goods	21.3	21.4
Inventory	93.9	82.0
Prepaid expenses and other current assets
Schedule Of Inventory [Line Items]
Inventory	92.4	80.6
Other long-term assets
Schedule Of Inventory [Line Items]
Inventory	$ 1.5	$ 1.4

Schedule Of Inventory [Line Items]

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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