Materials, energy and consumables used (Details) - ZAR (R) R in Millions	12 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Materials, energy and consumables used
Cost of raw materials	R 66,928	R 63,291	R 63,781
Cost of electricity and other consumables used in production process	9,678	8,145	7,539
Materials, energy and consumables used	R 76,606	R 71,436	R 71,320

The amount of raw materials and consumables used in the production process or in the rendering of services. [Refer: Current raw materials]

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 102
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_102&doctype=Standard
-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 99
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_99&doctype=Standard
-URIDate 2017-03-09

Name:	ifrs-full_RawMaterialsAndConsumablesUsed
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration