SHAREHOLDERS' EQUITY - Components of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Equity [Abstract]
Foreign currency translation	$ 8,853	$ 8,668	$ 2,684
Unrealized gain on deferred compensation contracts	489	988	652
Accumulated other comprehensive income	$ 9,342	$ 9,656	$ 3,336

Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant