Quarterly Financial Information (Unaudited) - Quarterly Financial Information (Detail) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2020 |
Sep. 30, 2020 |
Jun. 30, 2020 |
Mar. 31, 2020 |
Dec. 31, 2019 |
Sep. 30, 2019 |
Jun. 30, 2019 |
Mar. 31, 2019 |
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Quarterly Financial Information Disclosure [Abstract] | |||||||||||
| Research and development | $ 2,347 | $ 1,891 | $ 1,103 | $ 1,541 | $ 1,763 | $ 1,824 | $ 2,032 | $ 4,055 | $ 6,882 | $ 9,674 | $ 5,868 |
| General and administrative | 2,374 | 1,863 | 1,815 | 1,816 | 1,446 | 1,893 | 1,630 | 1,885 | 7,868 | 6,854 | 6,945 |
| Total operating expenses | 4,721 | 3,754 | 2,918 | 3,357 | 3,209 | 3,717 | 3,662 | 5,940 | 14,750 | 16,528 | 12,813 |
| Other income (expense) | (3) | (10) | (4) | 37 | 15 | 44 | 38 | 36 | 20 | 133 | 126 |
| Net loss | $ (4,724) | $ (3,764) | $ (2,922) | $ (3,320) | $ (3,194) | $ (3,673) | $ (3,624) | $ (5,904) | $ (14,730) | $ (16,395) | $ (12,687) |
| Basic and diluted net loss per common share | $ (1.11) | $ (1.14) | $ (1.68) | $ (2.15) | $ (5.91) | $ (9.07) | $ (10.08) | $ (17.57) | $ (5.42) | $ (39.76) | $ (72.29) |
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- Definition Total costs of sales and operating expenses for the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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