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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, 2023	Dec. 31, 2022	Dec. 31, 2021
Percentage of Revenue [Member] | Falikang—Related party
Entity Wide Revenue Major Customer [Line Items]
Concentration risk, percentage	60.00%	51.00%	15.00%
Percentage of Revenue [Member] | Astellas-Related party [Member]
Entity Wide Revenue Major Customer [Line Items]
Concentration risk, percentage	17.00%	31.00%	57.00%
Percentage of Revenue [Member] | AstraZeneca [Member]
Entity Wide Revenue Major Customer [Line Items]
Concentration risk, percentage	8.00%	9.00%	20.00%
Percentage of Accounts Receivable [Member] | Falikang—Related party
Entity Wide Revenue Major Customer [Line Items]
Concentration risk, percentage	42.00%	65.00%
Percentage of Accounts Receivable [Member] | Astellas-Related party [Member]
Entity Wide Revenue Major Customer [Line Items]
Concentration risk, percentage	7.00%	9.00%
Percentage of Accounts Receivable [Member] | AstraZeneca [Member]
Entity Wide Revenue Major Customer [Line Items]
Concentration risk, percentage	33.00%	16.00%

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
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 825
-SubTopic 10
-Section 50
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-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 825
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-Section 50
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-Name Accounting Standards Codification
-Topic 275
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-Section 50
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-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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