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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 230
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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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

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

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Long-term Debt Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2013
Debt Instrument [Line Items]
Commitment fees	$ 30		$ 65	$ 0	$ 0
Amortization of debt discounts	794	$ 230	1,310	389
Total	10,164	4,334	18,219	7,106
Senior Loans [Member]
Debt Instrument [Line Items]
Interest expense, term loans	4,964	3,426	10,012	5,620
Junior Loans [Member]
Debt Instrument [Line Items]
Interest expense, term loans	905	678	1,842	1,097
Equipment Notes, Series A [Member]
Debt Instrument [Line Items]
Interest expense, term loans	2,698	0	3,881	0
Equipment Notes, Series B [Member]
Debt Instrument [Line Items]
Interest expense, term loans	$ 773	$ 0	$ 1,109	$ 0