v3.19.3

Note 2 - Summary of Significant Accounting Policies (Tables) | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2019 | Dec. 31, 2018
Notes Tables |  |
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] |
|  | As of December 31, 2018 |
|  | Level 1 |  |  | Level 2 |  |  | Level 3 |  |  | Total |
Financial liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant liability |  | $ | - |  |  | $ | - |  |  | $ | 140 |  |  | $ | 140 |
Total financial liabilities |  | $ | - |  |  | $ | - |  |  | $ | 140 |  |  | $ | 140 |
|  | As of December 31, 2017
|  | Level 1 |  | Level 2 |  | Level 3 |  | Total
Financial liabilities: |  |  |  |  |  |  |  |  |  |  |  |
Warrant liability |  | $ | — |  | $ | — |  | $ | 42 |  | $ | 42
Total financial liabilities |  | $ | — |  | $ | — |  | $ | 42 |  | $ | 42
|  | As of December 31, 2018
Financial liabilities: |  | Level 1 |  | Level 2 |  | Level 3 |  | Total
Warrant liability |  | $ | — |  | $ | — |  | $ | 140 |  | $ | 140
Total financial liabilities |  | $ | — |  | $ | — |  | $ | 140 |  | $ | 140
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] |
|  | Six Months Ended June 30, |
|  | 2018 |  | 2019 |
Fair value, beginning of period |  | $ | 42 |  | $ | 140 |
Change in fair value of preferred stock warrants |  | — |  | 106 |
Exchange of warrants upon Merger |  | — |  | (234 | )
Fair value at end of period |  | $ | 42 |  | $ | — |
|  | Six Months Ended June 30, |
|  | 2018 |  | 2019 |
Fair value, beginning of period |  | $ | — |  | $ | — |
Embedded derivative liability from the issuance of Notes |  | 496 |  | — |
Change in value of embedded derivatives |  | (60 | ) | — |
Fair value at end of period |  | $ | 436 |  | $ | — |
|  | Years Ended
|  | December 31,
|  | 2017 |  | 2018
Fair value, beginning of period |  | $ | 54 |  | $ | 42
Preferred stock warrants – exercised |  |  | (8) |  |  | —
Change in fair value of preferred stock warrants |  |  | (4) |  |  | 98
Fair value at end of period |  | $ | 42 |  | $ | 140
|  | Years Ended
|  | December 31,
|  | 2017 |  | 2018
Fair value, beginning of period |  | $ | — |  | $ | —
Embedded derivative liability from the issuance of Notes |  |  | — |  |  | 864
Change in value of embedded derivatives |  |  | — |  |  | (211)
Termination of the embedded derivative liability due to the extinguishment of the related Notes |  |  | — |  |  | (653)
Fair value at end of period |  | $ | — |  | $ | —

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- Definition Tabular disclosure of the fair value measurement of liabilities using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and gains or losses recognized in other comprehensive income (loss) and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs) by class of liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19279-110258 + Details
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- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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