Staff Costs - Summary of Staff Costs (Detail) - CNY (¥) ¥ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Analysis of income and expense [abstract]
Salaries, wages and welfare	¥ 24,647	¥ 22,445	¥ 21,400
Defined contribution retirement scheme	2,794	2,387	2,114
Other retirement welfare subsidy	206	197	194
Early retirement benefits (Note 47)	0	1	1
Staff costs	¥ 27,647	¥ 25,030	¥ 23,709

No definition available.

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The expense of all forms of consideration given by an entity in exchange for a service rendered by employees or for the termination of employment.

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The amount of post-employment benefit expense relating to defined contribution plans. Defined contribution plans are post-employment benefit plans under which an entity pays fixed contributions into a separate entity (a fund) and will have no legal or constructive obligation to pay further contributions if the fund does not hold sufficient assets to pay all employee benefits relating to employee service in the current and prior periods.

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A class of employee benefits expense that represents wages and salaries. [Refer: Employee benefits expense]

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Provision for early retirement benefits for eligible employees.

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The amount of employee expenses that the entity does not separately disclose in the same statement or note.

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