Note 3 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2018	Jun. 30, 2022 USD ($) shares	Dec. 31, 2021 USD ($)
Number Of Subsidiary Trusts	6
Percentage of Proceeds from Increased Rental Payments		20.00%
Cash		$ 3,600	$ 2,200
Cash and Cash Equivalents, at Carrying Value, Total		$ 11,704	12,642
Temporary Equity, Shares Outstanding (in shares) \| shares		169,733
Temporary Equity, Aggregate Amount of Redemption Requirement		$ 6,700
Temporary Equity, Shares Issued (in shares) \| shares		169,733
Subordinated Debt [Member]
Interest Payable		$ 21,400	$ 18,700

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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 interest payable on debt, including, but not limited to, trade payables.

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Aggregate amount of redemption requirements for each class or type of redeemable stock classified as temporary equity for each of the five years following the latest balance sheet date. The redemption requirement does not constitute an unconditional obligation that will be settled in a variable number of shares constituting a monetary value predominantly indexed to (a) a fixed monetary amount known at inception, (b) an amount inversely correlated with the residual value of the entity, or (c) an amount determined by reference to something other than the fair value of issuer's stock. Does not include mandatorily redeemable stock. The exception is if redemption is required upon liquidation or termination of the reporting entity.

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