XML 85 R71.htm IDEA: XBRL DOCUMENT v3.10.0.1
Stockholders’ Equity - Narartive 2 (Details) - shares
1 Months Ended 6 Months Ended 12 Months Ended
Jul. 31, 2016
Jun. 30, 2016
Dec. 31, 2018
May 31, 2018
May 31, 2016
May 31, 2014
May 31, 2013
May 31, 2012
May 31, 2011
Stock Compensation Plans                  
Shares reserved for future issuance related to stock plans     7,716,849            
Stock Incentive Plan 2010                  
Stock Compensation Plans                  
Shares authorized for issuance       36,753,475 30,753,475 24,753,475 21,753,475 16,553,475 12,553,475
Stock Options                  
Stock Compensation Plans                  
Expiration period 10 years 7 years              
Stock Options | Stock Incentive Plan 2010 | Non-employee Director                  
Stock Compensation Plans                  
Expiration period     10 years