Commitments and Contingencies - Additional Information (Detail) - USD ($) |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2018 |
Sep. 30, 2017 |
Dec. 31, 2017 |
|
| Facilities Operating Leases | |||||
| Other Commitments [Line Items] | |||||
| Operating lease expense | $ 378,000 | $ 182,000 | $ 1,000,000 | $ 387,000 | |
| Laboratory Equipment | |||||
| Other Commitments [Line Items] | |||||
| Property and equipment, gross | 237,000 | 237,000 | $ 171,000 | ||
| Accumulated amortization | $ 100,000 | $ 100,000 | $ 66,000 | ||
| X | ||||||||||
- Definition Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of operating lease expense. Excludes sublease income. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- 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. No definition available.
|
| X | ||||||||||
- Definition Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|