Note 6 - Commitments and Contingencies (Details Textual) - USD ($) |
1 Months Ended | 9 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|---|
Aug. 31, 2019 |
Sep. 30, 2019 |
Sep. 30, 2018 |
Dec. 31, 2018 |
Dec. 31, 2017 |
|
| Note To Financial Statement Details Textual | |||||
| Litigation Settlement, Amount Awarded from Other Party | $ 635,000 | ||||
| Proceeds from Legal Settlements | $ 443,000 | ||||
| Operating Lease, Expense | $ 282,000 | $ 174,000 | $ 232,000 | $ 225,000 | |