Other Current Assets (Schedule of Other Current Assets) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Prepaid expenses	$ 14.9	$ 12.0
Assets held for sale	4.6	0.0
Other	1.3	0.8
Total other current assets	$ 20.8	$ 12.8

Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

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Amount of current assets classified as other.

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Amount of other miscellaneous assets expected to be realized or consumed within one year or operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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