Long-Term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Principal, Total long-term debt	$ 202,525	$ 171,400
Discount and Deferred Financing Costs net, Total long-term debt	(12,544)	(7,214)
Balance, Total long-term debt	189,981	164,186
Principal, Less current portion	(1,500)	(1,750)
Discount and Deferred Financing Costs net, less current portion
Balance, net of discount, less current portion	(1,500)	(1,750)
Principal, Total long-term debt, non-current	201,025	171,400
Discount and Deferred Financing Costs net, Total long-term debt, non-current	(12,544)	(7,214)
Balance, net of discount, Total long-term debt, non-current	188,481	164,186
Note payable [Member]
Debt Instrument [Line Items]
Principal, Total long-term debt	2,525	2,525
Discount and Deferred Financing Costs net, Total long-term debt
Balance, Total long-term debt	2,525	2,525
Credit Facility [Member]
Debt Instrument [Line Items]
Principal, Total long-term debt	200,000	170,625
Discount and Deferred Financing Costs net, Total long-term debt	(12,544)	(7,214)
Balance, Total long-term debt	$ 187,456	$ 163,411