Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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No definition available.

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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Basis of Presentation (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Mar. 20, 2013
Debt Instrument [Line Items]
Retained deficit	$ (326,194)	$ (314,671)
9½% Senior Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Face amount of senior notes			$ 250,000
Interest rate of senior notes			9.50%
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] \| Accounting Standards Update 2014-09 [Member]
Debt Instrument [Line Items]
Retained deficit		$ 200