Long-Term Debt and Credit Facility - Components of Long-term debt (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Long-term debt:
Long-term debt	$ 64,912	$ 50,546
Less current portion of long-term debt	(50,228)	(32,291)
Long-term debt, less current portion	14,684	18,255
Revolving Credit Facility [Member]
Long-term debt:
Long-term debt	43,085	25,148
Term loan [Member]
Long-term debt:
Long-term debt	$ 21,827	$ 25,398