Fair Value Measurement of Financial Instruments - Analysis of Fair Value Measurement of Financial Assets (Detail) - CNY (¥) ¥ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of fair value measurement of assets [line items]
Net fair value gains recognized in profit or loss, before tax	¥ 2,894	¥ 5,495	¥ 4,442
less: current portion	(128,603)	(114,259)
Non-current portion	1,111	513
Financial assets at fair value through other comprehensive income, category [member]
Disclosure of fair value measurement of assets [line items]
Beginning balance	513
Additions	205
Maturity or disposal	(500)
Net fair value gains recognized in other comprehensive income, before tax	956
Exchange differences	(63)
Ending balance	1,111
Non-current portion	1,111	513
Financial assets at fair value through profit or loss, category [member]
Disclosure of fair value measurement of assets [line items]
Beginning balance	114,259
Additions	114,929
Maturity or disposal	(103,479)
Net fair value gains recognized in profit or loss, before tax	2,894
Ending balance	128,603
less: current portion	¥ (128,603)	¥ (114,259)

The amount of current financial assets measured at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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The fair value of financial assets. [Refer: At fair value [member]; Financial assets]

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The amount of financial assets at fair value through other comprehensive income. [Refer: At fair value [member]; Financial assets; Other comprehensive income]

+ References

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-Name IFRS
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The amount of financial assets that are measured at fair value and for which gains (losses) are recognised in profit or loss. A financial asset shall be measured at fair value through profit or loss unless it is measured at amortised cost or at fair value through other comprehensive income. A gain (loss) on a financial asset measured at fair value shall be recognised in profit or loss unless it is part of a hedging relationship, it is an investment in an equity instrument for which the entity has elected to present gains and losses in other comprehensive income or it is a financial asset measured at fair value through other comprehensive income. [Refer: At fair value [member]; Financial assets]

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The gains (losses) including exchange differences recognised in other comprehensive income on the fair value measurement of assets. [Refer: At fair value [member]; Other comprehensive income]

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The gains (losses) including exchange differences recognised in profit or loss on the fair value measurement of assets. [Refer: At fair value [member]]

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The gains (losses) on exchange differences, recognised in profit or loss, on the fair value measurement of assets. [Refer: At fair value [member]]

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The amount of non-current financial assets at fair value through other comprehensive income. [Refer: Financial assets at fair value through other comprehensive income]

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The increase in the fair value measurement of assets resulting from purchases of those assets. [Refer: At fair value [member]]

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The decrease in the fair value measurement of assets resulting from settlements. [Refer: At fair value [member]]

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