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Material Agreements - Additional Information (Detail) - USD ($) |  |  |  | 6 Months Ended |
--- | --- | --- | --- | --- | ---
Nov. 17, 2021 | Dec. 07, 2018 | Dec. 19, 2017 | Sep. 30, 2023 | Mar. 31, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Upfront, non-refundable payment |  |  | $ 30,000,000.0 |  |
Research and development and out-of-pocket (in percent) |  |  | 50.00% |  |
Cumulative milestone payments |  |  |  | $ 32,500,000 |
Purchase price |  | $ 37,800,000 |  |  |
Acquired in-process research and development |  |  |  | 12,500,000 |
HanAll Biopharma Co., Ltd |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Research and development payable |  |  |  | 0 | $ 0
Samsung Biologics Co., Ltd |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Purchase obligation, additional purchases, period (in years) | 4 years |  |  |  |
Purchase obligation, termination notice period (in days) | 30 days |  |  |  |
Purchase obligation, fees covered, termination period (in years) | 2 years |  |  |  |
Purchase obligation |  |  |  | $ 18,700,000 |
Maximum |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Consideration paid |  |  | $ 20,000,000.0 |  |
Maximum | Upon Achievement Of Development Regulatory And Sales Milestones |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Contingent milestone payments |  |  | $ 420,000,000.0 |  |

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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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 808 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479402/808-10-50-1 + Details
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