Debt and Other Obligations - Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Debt Instrument [Line Items]
Commitment fees	$ 30	$ 35
Amortization of debt discounts	1,231	516
Total	12,388	8,055
Senior Loans [Member]
Debt Instrument [Line Items]
Interest expense, term loans	4,672	5,048
Junior Loans [Member]
Debt Instrument [Line Items]
Interest expense, term loans	803	937
Fixed Rate Loan [Member]
Debt Instrument [Line Items]
Interest expense, term loans	159	0
Equipment Notes, Series A [Member]
Debt Instrument [Line Items]
Interest expense, term loans	4,308	1,183
Equipment Notes, Series B [Member]
Debt Instrument [Line Items]
Interest expense, term loans	$ 1,185	$ 336

Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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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.

+ References

No definition available.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Aggregate amount of interest paid or due on all long-term debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.8)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Amount of the fee for available but unused credit capacity under the credit facility.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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