Fair Value Measurement - Assets Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] ¥ in Thousands, $ in Thousands	Dec. 31, 2025 CNY (¥)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 CNY (¥)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	¥ 19,235,794	$ 2,750,682	¥ 21,681,502
Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents			7,188
Short-term investments	12,838,137	1,835,829	15,196,867
Adjustable-Rate Financial Products [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	4,264,781	609,856	6,471,968
Other long-term investments	2,124,783	303,840
Equity investments with readily determinable fair value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	8,093	$ 1,157	5,479
Fair Value Measurement Using Inputs Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	8,093		5,479
Fair Value Measurement Using Inputs Level 1 [Member] \| Equity investments with readily determinable fair value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	8,093		5,479
Fair Value Measurement Using Inputs Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	19,227,701		21,676,023
Fair Value Measurement Using Inputs Level 2 [Member] \| Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents			7,188
Short-term investments	12,838,137		15,196,867
Fair Value Measurement Using Inputs Level 2 [Member] \| Adjustable-Rate Financial Products [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	4,264,781		¥ 6,471,968
Other long-term investments	¥ 2,124,783