XML 96 R88.htm IDEA: XBRL DOCUMENT v3.20.2
Share-based payments (Details)
3 Months Ended 12 Months Ended
Mar. 31, 2020
item
shares
Dec. 31, 2019
$ / shares
Dec. 31, 2017
$ / shares
Dec. 31, 2014
$ / shares
Dec. 31, 2013
$ / shares
Dec. 31, 2012
$ / shares
2012 Employee Stock Option Plan (ESOP)            
Option plans            
Exercise price     $ 23.94     $ 13.65
2012 Employee Stock Option Plan (ESOP) | Minimum            
Option plans            
Exercise price       $ 34.09 $ 41.24  
2012 Employee Stock Option Plan (ESOP) | Maximum            
Option plans            
Percentage of instruments reserved (as percentage of total amount of shares) 7.00%          
Exercise price       $ 37.89 $ 46.57  
Vesting period 4 years          
2015 Restricted Stock Unit Plan (RSU)            
Option plans            
Number of vesting | item 3          
2015 Restricted Stock Unit Plan (RSU) | Maximum            
Option plans            
Number of instruments reserved | shares 2,100,000          
Vesting period 2 years          
2019 Employee Stock Option Plan (ESOP)            
Option plans            
Exercise price   $ 16.75        
Number of vesting | item 2          
2019 Employee Stock Option Plan (ESOP) | Maximum            
Option plans            
Number of instruments reserved | shares 3,100,000          
Vesting period 4 years