INCOME TAXES - Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Total expense (benefit) reconciliation
Total expense (benefit) computed by applying federal rates	$ 71,325	$ 40,445	$ 22,381
State and provincial income taxes, net of federal benefit	874	304	135
Excess depletion	(1,812)	(1,291)	(867)
Estimates for uncertain tax positions	(26,179)	(11,146)	3,180
Statutory tax attributable to non-controlling interest	(72)	654	1,013
Effect of foreign earnings	(7,659)	(8,249)	(6,921)
Unrealized foreign exchange gains	(616)	(286)	(38)
Effects of Swiss income tax reform		(72,669)
Changes in estimates	(858)	24	(1,538)
Valuation allowance	1,284	47,840	(47)
Other	580	720	200
Total income tax expense (benefit)	$ 36,867	$ (3,654)	$ 17,498

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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 unrealized foreign exchange gains (losses).

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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