Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Allowance for trade accounts receivable	$ 1,519	$ 1,523
Current portion of long-term debt, net of discounts of $990 and $1,657, respectively	990	1,657
Discounts and deferred financing costs	$ 8,143	$ 10,244
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	80,000,000	80,000,000
Common stock, shares issued	26,644,130	26,371,572
Common stock, shares outstanding	26,470,750	26,219,129
Treasury stock, shares	173,380	152,443