Note 4 - Capital Disclosures (Details Textual) - USD ($) |
Jun. 30, 2018 |
May 30, 2018 |
Mar. 31, 2018 |
Mar. 28, 2018 |
Dec. 31, 2017 |
|---|---|---|---|---|---|
| Statement Line Items [Line Items] | |||||
| Maximum equity authorised | $ 100,000,000 | ||||
| Total cash | $ 1,053,000 | $ 3,225,000 | |||
| Total cash equivalents | $ 16,891,000 | $ 7,406,000 | |||
| Investments, Interest Rate | 1.45% | 1.45% | |||
| Aspire purchase agreement 2018 [member] | |||||
| Statement Line Items [Line Items] | |||||
| Sale of Stock, Maximum Offering Value | $ 20,000,000 | ||||
| Cantor Fitzgerald [member] | |||||
| Statement Line Items [Line Items] | |||||
| Sale of Stock, Maximum Offering Value | $ 30,000,000 |
| X | ||||||||||
- Definition The interest rate applicable to investments held by the entity. No definition available.
|
| X | ||||||||||
- Definition The maximum number of equity permitted to be issued by an entity's charter and bylaws. No definition available.
|
| X | ||||||||||
- Definition The maximum offering value allowed under an equity facility. No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition The amount of cash on hand and demand deposits. [Refer: Cash on hand] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition The amount of short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|