v3.22.2.2

Note 2 - Investments and Fair Value Measurement - Summary of Cash, Cash Equivalents and Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Cash and cash equivalent, fair value		$ 12,663
Total cash, cash equivalents and restricted cash	$ 17,732	12,663	$ 13,271	$ 27,274
Total cash, cash equivalents, restricted cash and short-term investments, amortized cost	20,926	51,630
Total cash, cash equivalents, restricted cash and short-term investments, fair value	20,926	51,630
Marketable Securities [Member]
Short-term investment, amortized Cost	3,194	38,967
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Short-term investment, fair value	3,194	38,967
Commercial Paper [Member] | Marketable Securities [Member]
Short-term investment, amortized Cost	3,194	29,504
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Short-term investment, fair value	3,194	29,504
Corporate Debt Securities [Member] | Marketable Securities [Member]
Short-term investment, amortized Cost		9,463
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Short-term investment, fair value		9,463
Cash and Cash Equivalents [Member] | Cash [Member]
Cash, amortized cost	4,533	1,443
Cash and cash equivalent, fair value	4,533	1,443
Cash and Cash Equivalents [Member] | Money Market Funds [Member]
Cash and cash equivalent, fair value	113	2,822
Money market funds, amortized cost	113	2,822
Cash and Cash Equivalents [Member] | US Government Agencies Debt Securities [Member]
Cash and cash equivalent, fair value	7,193
U.S. government agency securities	7,193
Cash and Cash Equivalents [Member] | Commercial Paper [Member]
Cash and cash equivalent, fair value	5,893	8,398
Commercial paper, amortized cost	$ 5,893	$ 8,398

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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.

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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.

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Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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