STOCK BASED COMPENSATION - Narrative (Details) - USD ($)
12 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Authorized shares available for future issuance (in shares) 9,990,032    
Proceeds from exercise of stock options $ 179,000 $ 831,000 $ 1,539,000
Stock options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Aggregate intrinsic value of options exercised 3,900,000 10,800,000 102,000,000.0
Unrecognized compensation costs 0    
Restricted stock units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Unrecognized compensation costs 5,500,000    
Intrinsic value of RSU's vested 7,000,000.0 $ 6,000,000.0 $ 5,400,000
Total intrinsic value of all awards outstanding $ 14,400,000    
Weighted-average period for recognition 3 years 1 month 6 days    
2010 Plan | Stock options and RSUs      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 4 years    
2005 Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award expiration period 10 years    
Additional awards that may be granted (in shares) 0    
Minimum | 2010 Plan | Stock options and RSUs      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award expiration period 5 years    
Minimum | 2010 Plan | Stock options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Option price as percentage of fair market value on the date of grant 100.00%    
Maximum | 2010 Plan | Stock options and RSUs      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award expiration period 10 years    
First anniversary | 2005 Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting percentage 25.00%    
Monthly | 2005 Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 3 years