Note 1 - General (Details Textual) - USD ($) $ in Thousands, shares in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Apr. 30, 2019
Cash and Cash Equivalents, at Carrying Value, Ending Balance	$ 24,739	$ 15,601
Debt Securities, Trading, and Equity Securities, FV-NI, Total	4,549	$ 0
Lessee, Operating Lease, Discount Rate		12.00%
Operating Lease, Cost	500	$ 500
Operating Lease, Payments	$ 600	$ 600
Lessor, Operating Lease, Term of Contract (Month)			18 months
Bright Health [Member]
Investment Owned, Balance, Shares (in shares)	1.3
Debt Securities, Trading, and Equity Securities, FV-NI, Total	$ 4,500

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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Balance held at close of period in number of shares.

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Discount rate used by lessee to determine present value of operating lease payments.

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Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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