Stock-based Compensation - Expense Related to Stock Options (Detail) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2020 |
Jun. 30, 2019 |
Jun. 30, 2020 |
Jun. 30, 2019 |
|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
| Stock-based compensation expense related to stock options | $ 411 | $ 446 | $ 821 | $ 938 |
| Research and development, net | ||||
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
| Stock-based compensation expense related to stock options | 128 | 165 | 264 | 323 |
| Selling, general and administrative | ||||
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
| Stock-based compensation expense related to stock options | $ 283 | $ 281 | $ 557 | $ 615 |
| X | ||||||||||
- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| 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 | ||||||||||
- Details
|
| X | ||||||||||
- Details
|