v3.22.1

Fair Value Measurements - Schedule of Investments accounted at Fair Value (Detail) - Investment Accounted Fair Value [Member] ¥ in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2021 CNY (¥)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 CNY (¥)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Begining Balance		¥ 2,238		¥ 1,819
Additions		475		371
Disposals		(59)		(63)
Net unrealized fair value increase recognized in earnings		1,187		151
Foreign currency translation adjustments		(20)		(40)
Transition to assets categorized within level 1	[1]	(50)
Ending balance		¥ 3,771	$ 592	¥ 2,238
[1] The fair value hierarchy of certain equity investments were transferred from level 3 to level 1 due to the public listing of the investees during the year ended December 31, 2021

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Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset foreign currency translation adjustment.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

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