Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($)
$ in Thousands
Sep. 30, 2016
Dec. 31, 2015
Statement of Financial Position [Abstract]    
Accounts receivable, allowance $ 7,886 $ 7,691
Accumulated depreciation 84,940 76,680
Accumulated amortization $ 67,326 $ 53,747
Preferred stock, par value (in dollars per share) $ 0.01 $ 0.01
Preferred stock, shares authorized 10,000,000 10,000,000
Preferred stock, shares issued 0 0
Preferred stock, shares outstanding 0 0
Common stock, par value (in dollars per share) $ 0.01 $ 0.01
Common stock, shares authorized 200,000,000 200,000,000
Common stock, shares issued 48,049,000 47,709,000
Common stock, shares outstanding 48,049,000 47,709,000