LEASE (Details) - CNY (¥) ¥ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
LEASE
Rental income recognized	¥ 330	¥ 318	¥ 240

The amount of operating lease income. Operating lease is a lease that does not transfer substantially all the risks and rewards incidental to ownership of an underlying asset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2020-01-01
-Paragraph 90
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2020-en-r&anchor=para_90_b&doctype=Standard
-URIDate 2020-01-01

Name:	ifrs-full_OperatingLeaseIncome
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration