SHAREHOLDERS' EQUITY - Components of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Stockholders' Equity Note [Abstract]
Foreign currency translation	$ 8,580	$ 2,684	$ 4,573
Unrealized gain on deferred compensation contracts	988	652	495
Accumulated other comprehensive income	$ 9,568	$ 3,336	$ 5,068

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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