Earnings per share (Details) - shares shares in Millions	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
(Loss) / profit per share attributable to equity holders of the parent: (ii)
Weighted average outstanding shares	588	575	575
Adjustments for calculation of diluted earnings per share Treasury shares		2
Weighted - average diluted common shares	588	577	575

The weighted average number of ordinary shares outstanding plus the weighted average number of ordinary shares that would be issued on the conversion of all the dilutive potential ordinary shares into ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 33
-IssueDate 2020-01-01
-Paragraph 70
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2020-en-r&anchor=para_70_b&doctype=Standard
-URIDate 2020-01-01

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration