Tax Benefit (expense) Allocated to each Component of Other Comprehensive Income (loss) (Detail) ¥ in Millions, $ in Millions	12 Months Ended
Dec. 31, 2024 CNY (¥)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 CNY (¥)	Dec. 31, 2022 CNY (¥)
Other Comprehensive Income (Loss), Tax [Abstract]
Unrealized gains (losses) on available-for-sale investments	¥ (18)	$ (2)	¥ (13)	¥ 28
Net current-year other comprehensive income (loss)	¥ (18)	$ (2)	¥ (13)	¥ 28

Amount, before adjustment, of tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 12
-SubTopic 10
-Topic 220
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-12

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Balance Type:	debit
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