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Note 2 - Summary of Significant Accounting Policies (Details Textual) - $ / shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Minimum Percentage of Ownership in Order to Qualify as Controlling Interest	9.00%
Performance Fee Adjustment, Variable Rate	0.15%
Performance Fee Adjustment, Measurement Period (Year)	36 years
Number of Reporting Units	1
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 1.5	$ 1.5

X

- Definition

Represents the minimum percentage of ownership in order to qualify as controlling interest.

+ References

No definition available.

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X

- Definition

The base performance measurement period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days, used to calculate the performance fee adjustment.

+ References

No definition available.

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- Definition

Variable rate for calculation of the performance fee adjustment component of the investment advisory fee under the Mutual Fund Performance Fee arrangement.

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No definition available.

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- Definition

Face amount or stated value per share of common stock.

+ 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(29))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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- Definition

Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

+ References

No definition available.

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