Quarterly report pursuant to Section 13 or 15(d)

Stock Plans (Details 1)

v3.3.0.814
Stock Plans (Details 1) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2015
Sep. 30, 2014
Sep. 30, 2015
Sep. 30, 2014
Share-based Goods and Nonemployee Services Transaction [Line Items]        
Weighted-average risk-free interest rate 1.70% 1.70% 1.80% 2.00%
Expected dividend payments $ 0 $ 0 $ 0 $ 0
Expected holding period (years) [1] 4 years 6 months 4 years 2 months 12 days 6 years 4 months 24 days 6 years 6 months
Weighted-average volatility factor [2] 1.65% 1.66% 1.61% 1.66%
Estimated forfeiture rates [3] 30.00% 31.00% 30.00% 31.00%
[1] Expected holding periods are based on the simplified method provided in Staff Accounting Bulletin No. 107 for "plain vanilla options.”
[2] Weighted average volatility is based on the historical volatility of our common stock
[3] Estimated forfeiture rates are based on historical data