INCOME TAXES - Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Total expense (benefit) reconciliation
Total expense computed by applying federal rates	$ 40,445	$ 22,381	$ (29,343)
State and provincial income taxes, net of federal benefit	304	135	(104)
Excess depletion	(1,291)	(867)	(1,440)
Estimates for uncertain tax positions	(11,146)	3,180	8,574
Statutory tax attributable to non-controlling interest	654	1,013	1,736
Effect of foreign earnings	(8,249)	(6,921)	1,230
Effect of foreign earnings indefinitely reinvested			(19,004)
Realized foreign exchange gains			18,330
Unrealized foreign exchange gains	(286)	(38)	(1,610)
Effects of US income tax reform			30,675
Effects of Swiss income tax reform	(72,669)
Changes in estimates	24	(1,538)	(70)
Valuation allowance	47,840	(47)	6,337
Other	720	200	(539)
Total income tax (benefit) expense	$ (3,654)	$ 17,498	$ 14,772

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to realized foreign exchange gains (losses).

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to Tax Cuts and Jobs Act.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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