Long-Term Debt - Future Contractual Principal Payments (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Future contractual principal payments on long term debt
2018	$ 8
2019	8
2020	200,009
2021	9
Total	$ 200,034	$ 34

Amount of long-term debt and capital lease obligations including current maturities.

No definition available.

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- Definition

Principal amount of long-term debt and capital lease obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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- Definition

Principal amount of long-term debt and capital lease obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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- Definition

Principal amount of long-term debt and capital lease obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of long-term debt and capital lease obligation maturing in the remainder of the fiscal year following the latest fiscal year ended.

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No definition available.

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No definition available.

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