Note 4 - Real Property and Other Income, Expense (Details Textual) $ in Millions	Sep. 30, 2025 USD ($) ft²	Dec. 31, 2024 USD ($)
Lessor, Operating Lease, Payment to be Received, Remainder of Fiscal Year	$ 0.2
Lessor, Operating Lease, Payment to be Received, Year One	0.8
Lessor, Operating Lease, Payment to be Received, Year Two	0.6
Lessor, Operating Lease, Payment to be Received, Year Three	0.4
Lessor, Operating Lease, Payment to be Received, Year Four	0.5
Lessor, Operating Lease, Payment to be Received, Year Five	$ 1.0
Office Building [Member] \| TEXAS
Net Rentable Area (Square Foot) \| ft²	90,000
Percentage of Occupancy	25.00%
Accrual for Taxes Other than Income Taxes, Current	$ 0.2	$ 0.3

Percentage of occupancy.

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- Definition

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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(20))
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 720
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483384/720-30-45-1

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
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-Name Accounting Standards Codification
-Section 45
-Paragraph 8
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483467/210-10-45-8

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- Definition

Amount of lease payment to be received by lessor for operating lease in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479773/842-30-50-12

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- Definition

Amount of lease payment to be received by lessor for operating lease in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lease payment to be received by lessor for operating lease in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lease payment to be received by lessor for operating lease in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 30
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-Section 50
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-URI https://asc.fasb.org/1943274/2147479773/842-30-50-12

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Amount of lease payment to be received by lessor for operating lease in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lease payment to be received by lessor for operating lease in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Net rentable area for properties owned.

+ References

No definition available.

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