CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 1,269	$ 763
Preferred stock, par value (usd per share)	$ 0.01	$ 0.01
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Common stock, par value (usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	97,200,000	90,900,000
Common stock, shares outstanding (in shares)	96,700,000	90,300,000
Common stock shares outstanding, subject to repurchase (in shares)	100,000	300,000
Treasury stock, shares (in shares)	500,000	500,000