Long-term provisions - Environmental provisions, Risk-free rates and Impact of changes to discount rates (Details) - ZAR (R) R in Millions	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Provisions
Provisions	R 19,960	R 17,727	R 18,779
Environmental
Provisions
Provisions	18,742	14,933	R 15,716
Investments restricted for mining rehabilitation purposes	667	649
Indemnities for mining rehabilitation purposes	R 2,155	R 2,066
Assumed percentage change in discount rate	1.00%	1.00%
Increase in the discount rate	R (3,351)	R (2,726)
amount capitalised to property, plant and equipment	(1,930)	(1,434)
income recognised in income statement	(1,421)	(1,292)
Decrease in the discount rate	4,540	3,786
amount capitalised to property, plant and equipment	2,622	2,058
expense recognised in income statement	R 1,918	R 1,728
Minimum \| Environmental \| South Africa
Provisions
Risk-free interest rate used to discount estimated cash flows related to provisions	6.90%	7.30%
Minimum \| Environmental \| Europe
Provisions
Risk-free interest rate used to discount estimated cash flows related to provisions	0.00%	0.00%
Minimum \| Environmental \| United States of America
Provisions
Risk-free interest rate used to discount estimated cash flows related to provisions	1.70%	2.60%
Minimum \| Environmental \| Canada
Provisions
Risk-free interest rate used to discount estimated cash flows related to provisions	1.70%	2.00%
Maximum \| Environmental \| South Africa
Provisions
Risk-free interest rate used to discount estimated cash flows related to provisions	8.70%	9.20%
Maximum \| Environmental \| Europe
Provisions
Risk-free interest rate used to discount estimated cash flows related to provisions	0.70%	1.50%
Maximum \| Environmental \| United States of America
Provisions
Risk-free interest rate used to discount estimated cash flows related to provisions	2.30%	3.00%
Maximum \| Environmental \| Canada
Provisions
Risk-free interest rate used to discount estimated cash flows related to provisions	2.20%	2.70%

- Definition

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

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- Definition

The amount of effect on the long term provisions due to decrease in the discount rate.

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- Definition

The amount of income recognised in income statement on the long term provisions due to decrease in the discount rate.

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- Definition

The amount capitalised to property, plant and equipment on the long term provisions due to decrease in the discount rate.

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The amount of effect on the long term provisions due to increase in the discount rate.

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The amount of income recognised in income statement on the long term provisions due to increase in the discount rate.

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- Definition

The amount capitalised to property, plant and equipment on the long term provisions due to increase in the discount rate.

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- Definition

The amount of indemnities for rehabilitation.

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- Definition

Investments restricted for mining rehabilitation purposes.

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- Definition

The aggregate of provisions which mature over a period greater than one year. This amount includes the noncurrent and current portion of long-term provisions.

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The assumed percentage change in the discount rate used to calculate the impact on the provision.

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The risk free rates used to discount the estimated cash flows related to provisions.

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