XML 77 R61.htm IDEA: XBRL DOCUMENT v3.8.0.1
Share-Based Payments - Additional Information (Details) - USD ($)
12 Months Ended
Jan. 01, 2018
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Options to purchase shares of common stock (in shares)   1,620,652    
Tax benefits related to stock based compensation   $ 0 $ 0 $ 0
Expected contractual term   10 years    
Expected dividend yield   0.00% 0.00% 0.00%
Restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Total unrecognized compensation expense related to stock option   $ 2,400,000    
Weighted-average period to recognize compensation expense   1 year 2 months 9 days    
Performance-Based Stock Units (PSUs)        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Total unrecognized compensation expense related to stock option   $ 9,300,000    
2007 Plan and 2013 Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share based awards reserved for issuance (in shares)   7,206,938    
Shares available for future issuance under 2013 ESPP (in shares)   1,327,606    
2013 Stock Incentive Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Annual increase in common stock (in shares)   2,000,000    
Percentage of outstanding shares of common stock (in shares)   4.00%    
Weighted-average grant date fair value of options (in usd per share)   $ 35.24 $ 28.41 $ 65.38
Intrinsic value of options exercised   $ 31,500,000 $ 26,400,000 $ 50,900,000
Total unrecognized compensation expense related to stock option   $ 85,300,000    
Weighted-average period to recognize compensation expense   2 years 4 months 30 days    
2013 Stock Incentive Plan | Performance-based stock options        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Options to purchase shares of common stock (in shares)   0 0 0
Employee Stock Purchase Plan 2013        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Shares available for future issuance under 2013 ESPP (in shares)   213,791    
Stock purchase offering period   6 months    
Purchase price discount rate for stock options   85.00%    
Shares issued under 2013 ESPP (in shares)   59,651 36,680  
Opportunity to purchase common stock (in shares)   327,272    
Subsequent Event | 2013 Stock Incentive Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Additional shares authorized for issuance (in shares) 1,953,046