Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
Amounts due under the Credit Facility	$ 55,787	$ 55,787
PIK interest payable related to the Credit Facility	27,178	11,582
Plus: 2% exit fee on Credit Facility	254
6% convertible senior unsecured notes due 2021		71,865
Gross long-term debt	83,219	139,234
Less: discount on Credit Facility	(5,114)
Less: total debt issuance costs	(166)	(1,272)
Long-term debt, less issuance costs	$ 77,939	$ 137,962