Amount authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

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Per share amount of share repurchase by investment company. Includes, but is not limited to, per unit, membership interest, or other ownership interest.

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Date of repurchase agreement, in YYYY-MM-DD format.

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Per share or per unit amount of equity securities issued.

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Number of shares issued which are neither cancelled nor held in the treasury.

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Number of shares that have been repurchased and retired during the period.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Note 9 - Share Buybacks (Details Textual) - USD ($)							1 Months Ended	2 Months Ended
Note 9 - Share Buybacks (Details Textual) - USD ($)	Feb. 14, 2020	Dec. 16, 2019	Oct. 24, 2018	Nov. 10, 2017	Apr. 26, 2016	Dec. 22, 2014	Sep. 30, 2016	Dec. 31, 2017	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2020	Dec. 31, 2018	Aug. 31, 2018	Dec. 31, 2014
Shares, Outstanding (in shares)									7,016,432	7,016,432
Investment Company, Share Repurchase Plan [Member]
Repurchase Agreement, Date				Nov. 10, 2017	Apr. 26, 2016
Repurchase Agreement, Date of Repurchase			Aug. 31, 2018				Sep. 30, 2016
Stock Repurchased and Retired During Period, Shares (in shares)							272,008	128,551
Stock Repurchased During Period, Value							$ 2,000,000	$ 1,100,000
Shares, Outstanding (in shares)								7,302,146
Investment Company, Share Repurchase Plan [Member] \| Maximum [Member]
Stock Repurchase Program, Authorized Amount				$ 2,000,000	$ 2,000,000								$ 2,000,000
Investment Company, Modified Dutch Auction Tender Offer [Member]
Stock Repurchase Program, Authorized Amount		$ 2,000,000				$ 5,044,728
Stock Repurchased During Period, Value			$ 2,000,000
Shares, Outstanding (in shares)											6,893,056	7,178,770
Stock Repurchased During Period, Shares (in shares)	285,714		123,376			859,468
Investment Company, Share Repurchase, Per Share (in dollars per share)	$ 7	$ 0.1	$ 16.21
Stock Repurchase, Purchase Price of Common Stock, Percent						95.00%
Shares Issued, Price Per Share (in dollars per share)														$ 23.2702
Investment Company, Modified Dutch Auction Tender Offer [Member] \| Maximum [Member]
Investment Company, Share Repurchase, Per Share (in dollars per share)		8
Investment Company, Modified Dutch Auction Tender Offer [Member] \| Minimum [Member]
Investment Company, Share Repurchase, Per Share (in dollars per share)		$ 6
Investment Company, Tender Offer [Member] \| Maximum [Member]
Stock Repurchase Program, Authorized Amount						$ 20,000,000