Restricted Investments - Reconciliation of Movement in Investments Held by Environmental Trust Funds (Details) - ZAR (R) R in Millions	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2023
Disclosure of financial assets [line items]
Restricted investments	R 6,731	R 6,044
Fair value gain through profit and loss	260	104	R 219
Total environmental trust funds
Disclosure of financial assets [line items]
Restricted investments	6,716	6,030	5,673
Interest income	369	329	R 258
Fair value gain through profit and loss	254	95
Fair value gain through other comprehensive income	48	18
Dividends received	16	15
Maturity of equity-linked deposits	0	(96)
Acquisition/(maturity) of fixed deposits	84	(5)
Maturity of collective investment schemes (unit trusts)	0	(138)
Acquisition of government bonds	32	145
Net transfer of cash equivalents	(117)	93
Withdrawal of funds for rehabilitation work performed	R 0	R (99)

Decrease Through Withdrawal of Funds for Environmental Rehabilitation

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Increase (Decrease) Through Acquisition (Disposal) of Cash and Cash Equivalents

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Increase (Decrease) Through Equity-Linked Deposits Acquired (Matured( , Financial Assets

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Increase (Decrease) Through Fixed Deposits Acquired (Matured), Financial Assets

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Increase (Decrease) Through government bond Acquired (Matured), Financial Assets

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Increase (Decrease) Through unit trusts Acquired (Matured), Financial Assets

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Restricted Investments1

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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The amount of dividends received.

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The gains (losses) on financial assets at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

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The gains (losses) recognised in other comprehensive income on financial assets measured at fair value through other comprehensive income applying paragraph 4.1.2A of IFRS 9, net of tax, before reclassification adjustments. [Refer: Financial assets measured at fair value through other comprehensive income; Other comprehensive income]

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The amount of income arising from interest.

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