CONDENSED FINANCIAL INFORMATION OF THE PARENT COMPANY (Details) - USD ($)
$ in Thousands
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2015
ASSETS        
Cash and cash equivalents $ 265,675 $ 197,640 $ 229,095 $ 207,834
Prepaid expenses 713 619    
Total current assets 1,000,898 865,356    
Total assets 1,210,128 1,058,254    
LIABILITIES AND STOCKHOLDERS' EQUITY        
Accrued payroll and related expense 14,299 13,600    
 Derivative financial liability 412 487    
Total current liabilities 333,054 302,978    
Long-term loan 20,709 20,581    
Total liabilities 367,775 334,714    
Equity:        
Ordinary shares, par value $0.001 per share, 100,000,000 shares authorized; 60,342,099 shares issued and outstanding as of June 30, 2017 and 2018, respectively 60 60    
Additional paid-in capital 223,396 222,189    
Accumulated other comprehensive loss (5,453) (22,859)    
Total equity 842,353 723,540 682,685 585,385
Total liabilities and equity 1,210,128 1,058,254    
Parent Company [Member]        
ASSETS        
Cash and cash equivalents 21,578 13,103 $ 8,571 $ 8,437
Amounts due from subsidiaries 53,503 59,920    
Prepaid expenses 61 61    
Total current assets 75,142 73,084    
Investments in subsidiaries 869,706 726,837    
Total assets 944,848 799,921    
LIABILITIES AND STOCKHOLDERS' EQUITY        
Accrued payroll and related expense 28 14    
 Derivative financial liability 412 487    
Amounts due to subsidiaries 82,491 55,869    
Total current liabilities 82,931 56,370    
Long-term loan 19,865 20,032    
Total liabilities 102,796 76,402    
Equity:        
Ordinary shares, par value $0.001 per share, 100,000,000 shares authorized; 60,342,099 shares issued and outstanding as of June 30, 2017 and 2018, respectively 60 60    
Additional paid-in capital 223,396 222,189    
Retained earnings 624,049 524,129    
Accumulated other comprehensive loss (5,453) (22,859)    
Total equity 842,052 723,519    
Total liabilities and equity $ 944,848 $ 799,921