STOCK BASED COMPENSATION - Stock-based compensation expense (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Jun. 30, 2015 |
Jun. 30, 2014 |
Jun. 30, 2013 |
|
| Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] | |||
| Stock-based compensation expense | $ 4,992 | $ 4,906 | $ 3,376 |
| Cost of sales | |||
| Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] | |||
| Stock-based compensation expense | 601 | 590 | 446 |
| Research and development | |||
| Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] | |||
| Stock-based compensation expense | 2,854 | 2,423 | 1,433 |
| Selling, general and administrative | |||
| Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] | |||
| Stock-based compensation expense | $ 1,537 | $ 1,893 | $ 1,497 |