Other Current Assets (Schedule of Other Current Assets) (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Prepaid expenses	$ 13.6	$ 12.0
Assets held for sale	4.6
Other	2.2	0.8
Total other current assets	$ 20.4	$ 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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-Name Accounting Standards Codification
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- References

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Amount of current assets classified as other.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
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