XML 84 R71.htm IDEA: XBRL DOCUMENT v3.3.1.900
Equity Award Plans - Summary of Assumptions used in the Black-Scholes Option-Pricing Model to Determine Fair Value of Common Shares to be Issued under the ESPP (Details) - $ / shares
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Fair value of common stock (usd per share) $ 0.00 $ 72.60 $ 5.71
Dividend yield   0.00% 0.00%
Minimum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Fair value of common stock (usd per share)   $ 27.89 $ 6.05
Risk-free interest rate   1.80% 0.60%
Expected term (in years)   4 years
Volatility   51.00% 46.00%
Maximum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Fair value of common stock (usd per share)   $ 75.87 $ 42.37
Risk-free interest rate   2.00% 2.10%
Expected term (in years)   6 years 6 years
Volatility   53.00% 54.00%
ESPP shares      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Fair value of common stock (usd per share)     $ 20.00
Risk-free interest rate   0.10% 0.10%
Dividend yield 0.00% 0.00% 0.00%
ESPP shares | Minimum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Fair value of common stock (usd per share) $ 19.10 $ 27.08  
Risk-free interest rate 0.09%    
Expected term (in years) 6 months 6 months 8 months 12 days
Volatility 38.00% 35.00% 42.00%
ESPP shares | Maximum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Fair value of common stock (usd per share) $ 35.16 $ 32.32  
Risk-free interest rate 0.50%    
Expected term (in years) 1 year 1 year 1 year 2 months 12 days
Volatility 42.00% 45.00% 45.00%