Note 3 - Investments - Portfolio Composition by Geographical Classification (Details) - USD ($)		Dec. 31, 2022	Dec. 31, 2021
Investment Owned, at Fair Value		$ 273,616,782	$ 301,603,725
Percentage of total investments		100.00%	100.00%
ARGENTINA
Investment Owned, at Fair Value	[1]	$ 17,575,152	$ 19,926,255
Percentage of total investments	[1]	6.30%	6.60%
BOTSWANA
Investment Owned, at Fair Value		$ 2,368,290	$ 4,740,000
Percentage of total investments		0.90%	1.60%
BRAZIL
Investment Owned, at Fair Value		$ 26,722,134	$ 27,331,410
Percentage of total investments		9.80%	9.10%
CABO VERDE
Investment Owned, at Fair Value		$ 17,834,541	$ 11,830,862
Percentage of total investments		6.50%	3.90%
CAMEROON
Investment Owned, at Fair Value		$ 14,476,312	$ 14,387,877
Percentage of total investments		5.30%	4.80%
CHILE
Investment Owned, at Fair Value		$ 970,393	$ 1,456,162
Percentage of total investments		0.40%	0.50%
COLOMBIA
Investment Owned, at Fair Value		$ 3,219,553	$ 5,342,393
Percentage of total investments		1.20%	1.80%
ECUADOR
Investment Owned, at Fair Value		$ 10,051,802	$ 12,387,189
Percentage of total investments		3.70%	4.10%
GHANA
Investment Owned, at Fair Value		$ 3,289,660	$ 8,367,480
Percentage of total investments		1.20%	2.80%
HONG KONG
Investment Owned, at Fair Value		$ 16,083,661	$ 22,884,859
Percentage of total investments		5.90%	7.60%
INDONESIA
Investment Owned, at Fair Value		$ 15,000,000	$ 15,000,000
Percentage of total investments		5.50%	5.00%
JERSEY
Investment Owned, at Fair Value		$ 13,750,000	$ 15,000,000
Percentage of total investments		5.00%	5.00%
KENYA
Investment Owned, at Fair Value		$ 4,926,482	$ 13,058,231
Percentage of total investments		1.80%	4.30%
MALAYSIA
Investment Owned, at Fair Value		$ 11,846,182	$ 17,537,201
Percentage of total investments		4.30%	5.80%
MEXICO
Investment Owned, at Fair Value		$ 41,842,987	$ 34,050,695
Percentage of total investments		15.30%	11.30%
MOROCCO
Investment Owned, at Fair Value		$ 628,862	$ 628,862
Percentage of total investments		0.20%	0.20%
NAMIBIA
Investment Owned, at Fair Value		$ 11,754,052	$ 15,184,914
Percentage of total investments		4.30%	5.00%
NETHERLANDS
Investment Owned, at Fair Value		$ 9,779,546	$ 9,278,031
Percentage of total investments		3.60%	3.10%
NIGERIA
Investment Owned, at Fair Value		$ 8,468,603	$ 10,182,138
Percentage of total investments		3.10%	3.40%
PERU
Investment Owned, at Fair Value		$ 3,502,265	$ 4,880,364
Percentage of total investments		1.30%	1.60%
ROMANIA
Investment Owned, at Fair Value		$ 6,279,305	$ 3,915,874
Percentage of total investments		2.30%	1.30%
SINGAPORE
Investment Owned, at Fair Value		$ 18,604,532	$ 17,634,943
Percentage of total investments		6.80%	5.80%
SOUTH AFRICA
Investment Owned, at Fair Value		$ 0	$ 497,462
Percentage of total investments		0.00%	0.20%
UNITED ARAB EMIRATES
Investment Owned, at Fair Value		$ 648,430	$ 648,430
Percentage of total investments		0.20%	0.20%
UGANDA
Investment Owned, at Fair Value		$ 11,325,748	$ 11,694,030
Percentage of total investments		4.10%	3.90%
Other Country [Member]
Investment Owned, at Fair Value		$ 2,668,290	$ 3,758,063
Percentage of total investments		1.00%	1.10%

[1] All of the Company’s investments in Argentina are Participations in trade finance facilities originated by IIG TOF B.V. See the Watch List Investments section in Part II, Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operations for further information.