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Segment and Geographic Information - Schedule of Customer Concentration by Collaboration Partners and Distribution Entity (Detail) - Customer Concentration Risk [Member]	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Percentage of Revenue [Member] | Astellas-Related party [Member]
Entity Wide Revenue Major Customer [Line Items]
Concentration risk, percentage	57.00%	21.00%	48.00%
Percentage of Revenue [Member] | AstraZeneca [Member]
Entity Wide Revenue Major Customer [Line Items]
Concentration risk, percentage	20.00%	37.00%	52.00%
Percentage of Revenue [Member] | Falikang—Related party
Entity Wide Revenue Major Customer [Line Items]
Concentration risk, percentage	15.00%	0.00%	0.00%
Percentage of Accounts Receivable [Member] | Astellas-Related party [Member]
Entity Wide Revenue Major Customer [Line Items]
Concentration risk, percentage	63.00%	10.00%
Percentage of Accounts Receivable [Member] | AstraZeneca [Member]
Entity Wide Revenue Major Customer [Line Items]
Concentration risk, percentage	34.00%	26.00%
Percentage of Accounts Receivable [Member] | Falikang—Related party
Entity Wide Revenue Major Customer [Line Items]
Concentration risk, percentage	0.00%	0.00%

X

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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- Definition

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+ References

No definition available.

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