Note 5 - Other Balance Sheet Information - Prepaid and Other Current Assets (Details) - USD ($) $ in Thousands |
Jun. 30, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|---|
| Prepaid clinical trial expenses | $ 435 | $ 5 | |
| Equity issuance costs | 343 | ||
| Prepaid insurance | 670 | ||
| Other prepaid expenses | 174 | 5 | |
| Total prepaid and other current assets | $ 1,622 | $ 10 | $ 34 |
| X | ||||||||||
- Definition Amount of equity issuance costs classified as current. No definition available.
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| X | ||||||||||
- Definition Amount of assets related to consideration paid in advance for clinical trials that provide economic benefits within a future period of one year or the normal operating cycle, if longer. No definition available.
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| X | ||||||||||
- Definition Amount of asset related to consideration paid in advance for other costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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