Details of Selected Balance Sheet Accounts - Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Details of Selected Balance Sheet Accounts [Abstract]
Income taxes receivable	$ 5,927	$ 430
Prepayments to vendors	2,962	877
Prepaid insurance	5,007	3,738
Prepaid non-income taxes	401	1,650
Other	3,757	4,479
Prepaid expenses and other current assets	$ 18,054	$ 11,174

Details of Selected Balance Sheet Accounts [Abstract]

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- Definition

Information pertaining to other prepaid expenses and current assets.

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- Definition

Prepaid Non-Income Taxes

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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 asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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

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

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