Restricted Investments - Reconciliation of Movement in Investments Held by Environmental Trust Funds (Details) - ZAR (R) R in Millions	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2024
Disclosure of financial assets [line items]
Restricted investments	R 7,320	R 6,731
Fair value gain through profit or loss1	156	260	R 104
Total environmental trust funds
Disclosure of financial assets [line items]
Restricted investments	7,303	6,716	6,030
Interest income	390	369	R 329
Fair value gain through profit or loss1	150	254
Fair value gain through other comprehensive income	32	48
Dividends received	15	16
Maturity of equity-linked deposits	(3)	0
Acquisition/(maturity) of fixed deposits	(18)	84
Acquisition of equity investments	30	0
Maturity of collective investment schemes (unit trusts)	(64)	0
Acquisition of government bonds	13	32
Net transfer of cash equivalents	R 42	R (117)

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

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Increase (Decrease) Through Equity Investments Acquired

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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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