Debt - Capital Lease Obligations and Other Narrative (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Subsidiary \| Capital lease obligations
Debt Instrument [Line Items]
Capital lease obligations	$ 2,082	$ 2,671

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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