Note 1 - Nature of the Business (Details Textual) - USD ($) |
1 Months Ended | 3 Months Ended | 9 Months Ended | |||||
|---|---|---|---|---|---|---|---|---|
Sep. 30, 2026 |
May 31, 2026 |
Dec. 31, 2024 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Dec. 31, 2025 |
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| Operating Income (Loss) | $ (6,347,000) | $ (5,648,000) | $ (13,755,000) | $ (15,588,000) | ||||
| Retained Earnings (Accumulated Deficit) | $ (325,896,000) | (325,896,000) | (325,896,000) | $ (308,296,000) | ||||
| Cash, Cash Equivalents, and Short-Term Investments | $ 9,900,000 | $ 9,900,000 | 9,900,000 | $ 5,200,000 | ||||
| Cash Provided by (Used in) Operating Activity, Including Discontinued Operation | $ (11,733,000) | $ (13,747,000) | ||||||
| Minimum Cash Balance For Loan Covenant | $ 2,000,000 | |||||||
| ATM Facility [Member] | ||||||||
| Stock Issued During Period, Shares, New Issues (in shares) | 216,161 | 757,875 | 216,161 | 2,095,070 | ||||
| Proceeds from Issuance of Common Stock | $ 1,000,000 | $ 3,300,000 | $ 1,000,000 | $ 8,400,000 | ||||
| Payments for Commissions | 15,000 | $ 100,000 | 15,000 | $ 100,000 | ||||
| Underwriting Agreement [Member] | ||||||||
| Stock Issued During Period, Shares, New Issues (in shares) | 1,219,513 | 1,000,000 | ||||||
| Proceeds from Issuance of Common Stock | $ 4,000,000 | $ 7,000,000 | $ 4,000,000 | $ 17,000,000 | ||||
| Payments for Commissions | $ 500,000 | |||||||
| X | ||||||||||
- Definition Minimum cash balance for loan covenant. No definition available.
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- Definition Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of cash inflow (outflow) from operating activity, including, but not limited to, discontinued operation. Operating activity includes, but is not limited to, transaction, adjustment, and change in value not defined as investing or financing activity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The net result for the period of deducting operating expenses from operating revenues. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The amount of cash paid for commissions during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The cash inflow from the additional capital contribution to the entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of accumulated undistributed earnings (deficit). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Number of new stock issued during the period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Details
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- Details
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