Note 5 - Pledged Assets - Schedule of Financial Instruments Owned and Pledged as Collateral (Details) - USD ($)	Mar. 31, 2025	Dec. 31, 2024
Investments, fair value	$ 4,279,414	$ 4,427,372
Accrued interest on pledged securities	587,536	601,640
Restricted cash	1,132,399	1,751,399
Assets	151,439,302	154,853,657
Asset Pledged as Collateral [Member]
Accrued interest on pledged securities	585,000	599,000
Restricted cash	1,132,000	1,751,000
Assets	122,523,000	124,443,000
Asset Pledged as Collateral [Member] | Securities Sold under Agreements to Repurchase [Member]
Accrued interest on pledged securities	585,000	599,000
Restricted cash	79,000	629,000
Assets	121,470,000	123,321,000
Asset Pledged as Collateral [Member] | Derivative [Member]
Accrued interest on pledged securities	0	0
Restricted cash	1,053,000	1,122,000
Assets	1,053,000	1,122,000
Asset Pledged as Collateral [Member] | Collateralized Mortgage-Backed Securities [Member] | Pass Through Certificate [Member]
Investments, fair value	118,704,000	119,960,000
Asset Pledged as Collateral [Member] | Collateralized Mortgage-Backed Securities [Member] | Pass Through Certificate [Member] | Securities Sold under Agreements to Repurchase [Member]
Investments, fair value	118,704,000	119,960,000
Asset Pledged as Collateral [Member] | Collateralized Mortgage-Backed Securities [Member] | Pass Through Certificate [Member] | Derivative [Member]
Investments, fair value	0	0
Asset Pledged as Collateral [Member] | Collateralized Mortgage-Backed Securities [Member] | Structured Finance [Member]
Investments, fair value	2,102,000	2,133,000
Asset Pledged as Collateral [Member] | Collateralized Mortgage-Backed Securities [Member] | Structured Finance [Member] | Securities Sold under Agreements to Repurchase [Member]
Investments, fair value	2,102,000	2,133,000
Asset Pledged as Collateral [Member] | Collateralized Mortgage-Backed Securities [Member] | Structured Finance [Member] | Derivative [Member]
Investments, fair value	$ 0	$ 0