Goodwill - Summary of Goodwill (Detail) - CNY (¥) ¥ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Changes in goodwill [abstract]
As of January 1	¥ 35,343	¥ 35,343
Additions	1
As of December 31	¥ 35,344	¥ 35,343

The amount of assets representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognised. [Refer: Business combinations [member]]

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