Income taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Jun. 30, 2025
Deferred tax assets
Tax losses	$ 418,331	$ 146,929
Unrealized foreign exchange losses	2,542	475
Capital raising costs	6,604	10,326
Loss Contingencies	0	6,000
Capital losses	8,676	29,302
Unrealized foreign exchange gains	611	0
Employee benefits	600	0
Other	20,513	3,846
Total deferred tax assets	457,877	196,879
Valuation allowance	(209,386)	(25,281)
Net deferred tax assets	248,491	171,598
Deferred tax liabilities
Property, plant and equipment	(214,182)	(142,893)
Unrealized foreign exchange gains	(525)	(5,511)
Employee Benefits	0	0
Convertible Notes	0	(3,704)
Financial Assets	(18,200)	(21,068)
Other	(46,416)	(6,394)
Total deferred tax liabilities	(279,323)	(179,570)
Total net deferred tax asset (liabilities)	$ (30,832)	$ (7,971)

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Deferred Tax Liabilities, Convertible Notes

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from unrealized losses on foreign currency transactions.

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