Note 4 - Real Property and Other Income, Expense (Details Textual) - Office Building [Member] - TEXAS	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Aug. 04, 2021 ft²
Net Rentable Area (Square Foot) \| ft²			90,000
Percentage of Occupancy	25.00%
Accrual for Taxes Other than Income Taxes, Current \| $	$ 338,000	$ 433,000

Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
-Topic 720
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-Section 45
-Paragraph 1
-Publisher FASB
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