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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Credit Risk and Concentration (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2017
Credit Risk and Concentration
Revenue, Practical Expedient, Financing Component [true false]	true
Cash and cash equivalents	$ 76,102	$ 96,316
Revenue \| Customer Concentration Risk
Credit Risk and Concentration
Concentration (as a percent)			13.00%
Foreign subsidiaries \| Cash and cash equivalents \| Cash and Cash Equivalents Concentration Risk
Credit Risk and Concentration
Concentration (as a percent)	63.00%	87.00%