Note 2 - Basis of Presentation and Significant Accounting Policies (Details Textual) $ in Thousands	Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)
Number of Wholly Owned Subsidiaries	8
Cash and Cash Equivalents, at Carrying Value, Ending Balance	$ 14,540		$ 23,319	$ 20,668
Restricted Cash, Current	286		282
Restricted Cash, Noncurrent	$ 1,202		$ 395
Immaterial Correction of Prior Period Financial Statements [Member]
Prepaid Expenses and Accrued Liabilities		$ 5,205

Represents the number of wholly owned subsidiaries of the reporting entity as of a certain date.

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Represents information related to prepaid expenses and accrued liabilities.

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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. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of cash restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Amount of cash restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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