Leases - Additional Information (Detail) ¥ in Millions, $ in Millions	12 Months Ended
Dec. 31, 2024 CNY (¥)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 CNY (¥)	Dec. 31, 2022 CNY (¥)
Leases [Abstract]
Operating lease, weighted average remaining lease term	12 years 8 months 12 days	12 years 8 months 12 days	13 years 7 months 6 days
Operating lease, weighted average discount rate	3.74%	3.74%	4.07%
Short-term lease cost	¥ 397	$ 54	¥ 547	¥ 424
Operating lease cost	¥ 3,800	$ 523	¥ 3,500	¥ 3,500

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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