Other Financial Information - Inventories, Net (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Schedule Of Inventory [Line Items]
Production and service materials	$ 76.6	$ 69.0
Finished goods	25.1	25.2
Inventory	101.7	94.2
Prepaid expenses and other current assets
Schedule Of Inventory [Line Items]
Inventory	97.3	90.6
Other long-term assets
Schedule Of Inventory [Line Items]
Inventory	$ 4.4	$ 3.6

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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