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Commitment and Contingencies - Additional Information (Detail) - USD ($) | 1 Months Ended | 3 Months Ended |
--- | --- | --- | ---
Apr. 30, 2017 | Feb. 28, 2017 | Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Contingencies And Commitments [Line Items] |  |  |  |  |
Research and development expense |  |  | $ 5,655,000 | $ 4,744,000 |
Sponsored Research Agreement [Member] |  |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |  |
Purchase commitment, amount | $ 499,000 |  |  |  |
Purchase commitment, period | 3 years |  |  |  |
Research and development expense |  |  | 42,000 | $ 42,000 |
Non-cancelable purchase commitments amount |  |  | 181,000 |  |
Non-cancelable purchase commitments amount, 2019 |  |  | 125,000 |  |
Non-cancelable purchase commitments amount, 2020 |  |  | 56,000 |  |
Indemnification Agreements [Member] |  |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |  |
Accrued liabilities |  |  | 0 |  | $ 0
Adimab Option Agreement [Member] |  |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |  |
Milestone payments |  | $ 25,000,000 |  |  |
Option fee |  | $ 250,000 |  |  |
Contract Manufacturing Organizations Agreement [Member] |  |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |  |
Non-cancelable purchase commitments amount |  |  | $ 250,000 |  | $ 250,000

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- Definition Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15(5)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.15(a)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 985 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 730 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373 + Details
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