Leases - Additional Information (Detail) - CNY (¥) ¥ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about depreciated charge of right-of-use assets recognized in the consolidated statement of comprehensive income [abstract]
Depreciation charge of right-of-use assets	¥ 26,012	¥ 22,751	¥ 0

The amount of depreciation of right-of-use assets. [Refer: Depreciation and amortisation expense; Right-of-use assets]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2020-01-01
-Paragraph 53
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2020-en-r&anchor=para_53_a&doctype=Standard
-URIDate 2020-01-01

Name:	ifrs-full_DepreciationRightofuseAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration