OTHER FINANCIAL STATEMENT DATA - Supplementary Cash Flow Activity (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Cash paid (received) for:
Interest	$ 7,022	$ 7,293	$ 7,660
Income taxes, net	2,397	2,314	2,237
Noncash investing activities:
Unpaid capital expenditures	$ 9,209	$ 2,774	$ 6,627

Future cash outflow to pay for purchases of fixed assets that have occurred.

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