Property, Equipment And Software - Schedule of property, equipment and software, net (Detail) ¥ in Thousands, $ in Thousands	Sep. 30, 2020 CNY (¥)	Sep. 30, 2020 USD ($)	Dec. 31, 2019 CNY (¥)
Property, Plant and Equipment, Net, by Type [Abstract]
Total property, equipment and software	¥ 51,668	$ 7,610	¥ 47,867
Less: accumulated depreciation and amortization	(25,935)	(3,820)	(18,221)
Net book value	25,733	3,790	29,646
Construction in progress	1,325	195	423
Total net book value of property, equipment and software	27,058	3,985	30,069
Laboratory Equipment [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property, equipment and software	27,336	4,026	24,265
Leasehold improvement [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property, equipment and software	12,605	1,857	11,856
Software [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property, equipment and software	10,201	1,502	10,220
Office furniture and equipment [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property, equipment and software	¥ 1,526	$ 225	¥ 1,526

Property plant and equipment net excluding construction in process.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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