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Retirement Benefit Obligation - Disclosure of the Effect of a Percentage Point Increase and Decrease in the Assumed Medical Cost Trend Rate (Details) - Medical cost trend rate - ZAR (R) R in Millions | Jun. 30, 2019 | Jun. 30, 2018
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Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Reasonably possible increase in actuarial assumption (as a percent) | 1.00% | 1.00%
Effect of a 1% increase on aggregate of service cost and finance costs | R 2 | R 2
Effect of a 1% increase on defined benefit obligation | R 23 | R 21
Reasonably possible decrease in actuarial assumption (as a percent) | 1.00% | 1.00%
Effect of a 1% decrease on aggregate of service cost and finance costs | R (2) | R (2)
Effect of a 1% decrease on defined benefit obligation | R (19) | R (18)

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- Definition Increase (Decrease) In Service And Finance Costs Due To Reasonably Possible Decrease In Actuarial Assumption + References No definition available. + Details
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- Definition Increase (Decrease) In Service And Finance Costs Due To Reasonably Possible Increase In Actuarial Assumption + References No definition available. + Details
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- 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. + References No definition available. + Details
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- Definition The increase (decrease) in a defined benefit obligation that would have been caused by a decrease in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 145 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_145_a&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The increase (decrease) in a defined benefit obligation that would have been caused by an increase in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 145 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_145_a&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The reasonably possible percentage of the decrease in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 145 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_145_a&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The reasonably possible percentage of the increase in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 145 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_145_a&doctype=Standard -URIDate 2018-03-16 + Details
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- Details
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