INCOME TAXES - Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Differences between provision for income taxes and income tax expense computed by applying federal rates
Total expense computed by applying federal rates	$ 22,381	$ (29,343)	$ 41,603
State and provincial income taxes, net of federal benefit	135	(104)	78
Excess depletion	(867)	(1,440)	(1,517)
Estimates for uncertain tax positions	3,180	8,574	2,870
Statutory tax attributable to non-controlling interest	1,013	1,736	3,162
Effect of foreign earnings	(6,921)	1,230	3,046
Effect of foreign earnings indefinitely reinvested		(19,004)	(22,922)
Realized foreign exchange gains		18,330
Unrealized foreign exchange gains	(38)	(1,610)	(746)
Effects of US income tax reform		30,675
Changes in estimates	(1,538)	(70)	(3,676)
Valuation allowance	(47)	6,337	4,374
Other	200	(539)	169
Total income tax expenses	$ 17,498	$ 14,772	$ 26,441

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

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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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