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STOCK-BASED COMPENSATION - Stock based compensation expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Stock based compensation expense
Stock-based compensation expense before taxes	$ 25,251	$ 23,846	$ 26,132
RSU
Stock-based compensation, other disclosures
Unrecognized compensation cost	13,300
Weighted-average period		2 years
Stock options
Stock-based compensation, other disclosures
Unrecognized compensation cost	500
Weighted-average period		1 year 9 months 18 days
Cost of goods sold
Stock based compensation expense
Stock-based compensation expense before taxes	732	$ 972	1,443
Selling, general and administrative
Stock based compensation expense
Stock-based compensation expense before taxes	23,876	22,293	21,354
Research and development
Stock based compensation expense
Stock-based compensation expense before taxes	$ 643	$ 581	433
Restructuring
Stock based compensation expense
Stock-based compensation expense before taxes			$ 2,902
2005 AS&E Plan and the 2014 AS&E Plan \| RSU
Stock based compensation expense
Granted (in shares)	0
2006 Plan
Stock based compensation expense
Granted (in shares)	0