STOCK BASED COMPENSATION - Summary of RSU activity (Details) - Restricted stock units - $ / shares
12 Months Ended
Jun. 30, 2015
Jun. 30, 2014
Jun. 30, 2013
Number of Shares      
Non-vested RSUs, Number of Shares, Beginning Balance 549,702 744,906 453,620
RSUs granted, Number of Shares 182,865 209,032 656,500
RSUs vested, Number of Shares (182,507) (170,197) (70,512)
RSUs canceled, Number of Shares (149,425) (234,039) (294,702)
Non-vested RSUs, Number of Shares, Ending balance 400,635 549,702 744,906
Weighted Average Grant Date Fair Value      
Non-vested RSUs, weighted average grant date fair value, Beginning balance, USD per share $ 22.65 $ 14.74 $ 9.42
RSUs granted, weighted average grant date fair value, USD per share 32.47 37.87 14.11
RSUs vested, weighted average grant date fair value, USD per share 21.27 15.59 14.14
RSUs cancelled, weighted average grant date fair value, USD per share 24.84 16.18 5.29
Non-vested RSUs, weighted average grant date fair value, Ending balance, USD per share $ 26.95 $ 22.65 $ 14.74