Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Details)

v3.7.0.1
Stock-Based Compensation (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Dec. 31, 2016
Jun. 30, 2016
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]          
Stock-based compensation expense $ 10,968 $ 8,417 $ 22,335   $ 15,933
Weighted Average Assumptions used in Black-Scholes Valuation Model [Abstract]          
Expected dividend yield 0.00% 0.00% 0.00%   0.00%
Risk-free interest rate 1.50% 1.00% 1.50%   1.00%
Expected volatility 46.10% 48.60% 46.40%   48.40%
Expected life 3 years 4 months 24 days 3 years 4 months 24 days 3 years 4 months 24 days   3 years 4 months 24 days
Forfeiture rate 0.00% 6.00% 0.00%   6.00%
ShippingEasy [Member]          
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]          
Stock-based compensation expense $ 1,200   $ 2,500 $ 1,900  
Employee and Director Stock Options [Member]          
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]          
Stock-based compensation expense 10,723 $ 8,154 21,858   $ 15,435
Employee Stock Purchases [Member]          
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]          
Stock-based compensation expense 245 263 477   498
Cost of Revenues [Member]          
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]          
Stock-based compensation expense 445 450 993   875
Sales and Marketing [Member]          
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]          
Stock-based compensation expense 1,975 1,857 4,282   3,588
Research and Development [Member]          
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]          
Stock-based compensation expense 2,221 1,425 4,717   2,780
General and Administrative [Member]          
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]          
Stock-based compensation expense $ 6,327 $ 4,685 $ 12,343   $ 8,690
Maximum [Member]          
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]          
Vesting period     5 years