Summary of significant accounting policies - Summary of Estimated Useful Life of Asset (Detail)	12 Months Ended
	Dec. 31, 2021
Lab Equipment [Member]
Property Plant And Equipment [Line Items]
Estimated useful life of asset	3 years
Computer Equipment [Member]
Property Plant And Equipment [Line Items]
Estimated useful life of asset	3 years
Vehicles [Member]
Property Plant And Equipment [Line Items]
Estimated useful life of asset	4 years
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Estimated useful life of asset	Shorter ofthe usefullife orremaininglease term
Minimum [Member] | Furniture and Office Equipment [Member]
Property Plant And Equipment [Line Items]
Estimated useful life of asset	3 years
Maximum [Member] | Furniture and Office Equipment [Member]
Property Plant And Equipment [Line Items]
Estimated useful life of asset	8 years