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v3.19.3

Provision for Silicosis Settlement - Disclosure of the Impact of a Reasonable Change in Certain Key Assumptions (Details) - ZAR (R) R in Millions | 12 Months Ended
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Jun. 30, 2019 | Jun. 30, 2018
Change in benefit take-up rate |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Increase in assumption (as a percent) | 10.00% | 10.00%
Decrease in assumption (as a percent) | 10.00% | 10.00%
Change in labour number |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Increase in assumption (as a percent) | 10.00% | 10.00%
Decrease in assumption (as a percent) | 10.00% | 10.00%
Change in disease risk |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Increase in assumption (as a percent) | 10.00% | 10.00%
Decrease in assumption (as a percent) | 10.00% | 10.00%
Change in disease progression rates |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Increase in progression period | 1 year | 1 year
Decrease in progression period | 1 year | 1 year
Change in benefit take-up rate |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Effect of an increase in the assumption | R 66 | R 65
Effect of a decrease in the assumption | (66) | (65)
Change in silicosis prevalence |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Effect of an increase in the assumption | 66 | 65
Effect of a decrease in the assumption | (66) | (65)
Change in disease progression rates |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Effect of an increase in the assumption | 33 | 31
Effect of a decrease in the assumption | R (33) | R (31)

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