Quarterly report pursuant to Section 13 or 15(d)

Condensed Consolidated Balance Sheets (Parenthetical)

v3.8.0.1
Condensed Consolidated Balance Sheets (Parenthetical) - USD ($)
$ in Thousands
Sep. 30, 2017
Dec. 31, 2016
Statement of Financial Position [Abstract]    
Accounts receivable, allowance for doubtful accounts $ 2,998 $ 2,468
Preferred stock, par value (in dollars per share) $ 0.001 $ 0.001
Preferred stock, shares authorized (in shares) 10,000,000 10,000,000
Preferred stock, shares issued (in shares) 0 0
Preferred stock, shares outstanding (in shares) 0 0
Common stock, par value (in dollars per share) $ 0.001 $ 0.001
Common stock, shares authorized (in shares) 125,000,000 125,000,000
Common stock, shares issued (in shares) 87,143,835 86,062,191
Common stock, shares outstanding (in shares) 83,130,124 81,087,353
Treasury stock (in shares) 4,013,711 4,974,838