Finance costs (Details) - CNY (¥) ¥ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Finance Cost [Abstract]
Interest and related expenses	¥ 115	¥ 120	¥ 99
Exchange gains	(7)	1	(2)
Finance costs	¥ 108	¥ 121	¥ 97

The amount of income or cost associated with interest and other financing activities of the entity.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2022-03-24
-Paragraph 85
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_85&doctype=Standard
-URIDate 2022-03-24

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration