v3.23.2

Note 2 - Investments and Fair Value Measurement - Summary of Cash, Cash Equivalents and Investments (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | --- | ---
Cash and cash equivalent, fair value |  | $ 12,663 |
Total cash, cash equivalents and restricted cash | $ 20,275 | 12,663 | $ 27,274
Total cash, cash equivalents, restricted cash and short-term investments | 20,770 | 51,630 |
Total cash, cash equivalents, restricted cash and short-term investments, fair value | 20,770 | 51,630 |
Marketable Securities [Member] |  |  |
Short-term investment, amortized Cost | 495 | 38,967 |
Short-term investment, fair value | 495 | 38,967 |
Gross Unrealized Gains | 0 | 0 |
Gross Unrealized Losses | 0 | 0 |
Commercial Paper [Member] | Marketable Securities [Member] |  |  |
Short-term investment, amortized Cost | 495 | 29,504 |
Short-term investment, fair value | 495 | 29,504 |
Gross Unrealized Gains | 0 | 0 |
Gross Unrealized Losses | 0 | 0 |
Corporate Debt Securities [Member] | Marketable Securities [Member] |  |  |
Short-term investment, amortized Cost |  | 9,463 |
Short-term investment, fair value |  | 9,463 |
Gross Unrealized Gains |  | 0 |
Gross Unrealized Losses |  | 0 |
Cash and Cash Equivalents [Member] | Cash [Member] |  |  |
Cash, amortized cost | 13,275 | 1,443 |
Cash and cash equivalent, fair value | 13,275 | 1,443 |
Cash and Cash Equivalents [Member] | Money Market Funds [Member] |  |  |
Cash and cash equivalent, fair value | 321 | 2,822 |
Money market funds, amortized cost | 321 | 2,822 |
Cash and Cash Equivalents [Member] | US Government Agencies Debt Securities [Member] |  |  |
Cash and cash equivalent, fair value | 2,444 |  |
U.S. government agency securities | 2,444 |  |
Cash and Cash Equivalents [Member] | Commercial Paper [Member] |  |  |
Cash and cash equivalent, fair value |  | 8,398 |
Short-term investment, amortized Cost | 4,235 |  |
Short-term investment, fair value | $ 4,235 |  |
Commercial paper |  | $ 8,398 |

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 + Details
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- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 + Details
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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 852 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481372/852-10-55-10 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 946 -SubTopic 830 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480167/946-830-55-12 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(4)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479617/946-210-S99-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 45 -Paragraph 21 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480555/946-210-45-21 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 45 -Paragraph 20 -SubTopic 210 -Topic 946 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480555/946-210-45-20 + Details
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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. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(9)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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