CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Allowance for doubtful accounts receivable	$ 1,550	$ 1,242
Par value of common stock (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	51,002,234	50,698,587
Common stock, shares outstanding (in shares)	50,340,853	50,037,206
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	1	1
Preferred stock, shares outstanding (in shares)	1	1
Treasury stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Treasury stock (in shares)	661,381	661,381