Other Balance Sheet Accounts - Other Current Assets (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Other Current Assets:
Non-trade receivables	$ 20.7	$ 25.0
Prepaid expenses and other current assets	13.9	9.2
Income taxes receivable	11.1	10.4
Total other current assets	$ 45.7	$ 44.6

Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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The sum of amounts currently receivable other than from customers. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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Amount of current assets classified as other.

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