Organization and Basis of Presentation - Summary of Cash Flow Statement of VIE and VIE's Subsidiaries (Detail) ¥ in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2024 CNY (¥)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 CNY (¥)	Dec. 31, 2022 CNY (¥)
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Net cash used in operating activities	¥ (92,300)	$ (12,640)	¥ (255,783)	¥ (456,808)
Net cash used in investing activities	(4,412)	(604)	(9,300)	(7,463)
Net cash generated from (used in) financing activities	(72)	(10)	(48,832)	(86,239)
VIE and VIE's subsidiaries [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Net cash used in operating activities	(160,551)	(21,994)	(2,768)	(139,381)
Net cash used in investing activities	(3,226)	(442)	(606)	(37,088)
Net cash generated from (used in) financing activities	¥ 0	$ 0	¥ (68,894)	¥ 377,630

Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 24
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-24

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Publisher FASB
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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