Long-term Debt - Obligations (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Obligations
Costs associated with issuances of debt	$ (3,410)	$ (3,983)
Total	117,618	156,744
Current portion of long-term debt and lease obligations	(459)	(40,024)
Non-current portion of long-term debt and lease obligations	117,159	116,720
Senior secured notes \| Senior secured second-priority lien notes (maturing December 15, 2021)
Obligations
Gross debt	120,569	120,569
Total		120,600
Senior secured notes \| Senior secured third-priority lien notes (redeemed on March 26, 2018)
Obligations
Gross debt	0	28,497
Total		28,500
Revolving line of credit (maturing August 22, 2019)
Obligations
Gross debt	0	10,000
Equipment capital leases and other debt
Obligations
Gross debt	$ 459	$ 1,661

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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

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