Other Assets and Liabilities Other Current Assets (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Total	$ 74.0	$ 49.3
Other Current Assets
Prepaid expenses	9.5	14.0
Short-term derivative assets	11.1	6.8
Income and other tax receivables	39.8	19.2
RINs Obligation surplus	8.7	4.9
Other	$ 4.9	$ 4.4

RINs Obligation Surplus, Other Assets, Current

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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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.

+ References

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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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