Note 6 - Fair Value - Schedule of Balance Sheet Grouping (Details) - USD ($)	Jun. 30, 2026	Dec. 31, 2025
Investments, fair value	$ 148,635	$ 225,436
Fair Value, Inputs, Level 1 [Member]
Investments, fair value	3,903
Fair Value, Inputs, Level 2 [Member]
Investments, fair value	0
Fair Value, Inputs, Level 3 [Member]
Investments, fair value	144,732
Advanced Materials Sector [Member] \| Fair Value, Inputs, Level 3 [Member]
Investments, fair value	100,000
Medical Devices Sector [Member] \| Fair Value, Inputs, Level 3 [Member]
Investments, fair value	0
Common Stock [Member] \| Fair Value, Inputs, Level 1 [Member]
Investments, fair value	0
Common Stock [Member] \| Fair Value, Inputs, Level 2 [Member]
Investments, fair value	0
Common Stock [Member] \| Fair Value, Inputs, Level 3 [Member]
Investments, fair value	141,197
Common Stock [Member] \| Advanced Materials Sector [Member] \| Fair Value, Inputs, Level 1 [Member]
Investments, fair value	0
Common Stock [Member] \| Advanced Materials Sector [Member] \| Fair Value, Inputs, Level 2 [Member]
Investments, fair value	0
Common Stock [Member] \| Advanced Materials Sector [Member] \| Fair Value, Inputs, Level 3 [Member]
Investments, fair value	141,197
Preferred Stock [Member] \| Fair Value, Inputs, Level 1 [Member]
Investments, fair value	0
Preferred Stock [Member] \| Fair Value, Inputs, Level 2 [Member]
Investments, fair value	0
Preferred Stock [Member] \| Fair Value, Inputs, Level 3 [Member]
Investments, fair value	0
Debt [Member] \| Fair Value, Inputs, Level 1 [Member]
Investments, fair value	0
Debt [Member] \| Fair Value, Inputs, Level 2 [Member]
Investments, fair value	0
Debt [Member] \| Fair Value, Inputs, Level 3 [Member]
Investments, fair value	3,535
Debt [Member] \| Medical Devices Sector [Member] \| Fair Value, Inputs, Level 1 [Member]
Investments, fair value	0
Debt [Member] \| Medical Devices Sector [Member] \| Fair Value, Inputs, Level 2 [Member]
Investments, fair value	0
Debt [Member] \| Medical Devices Sector [Member] \| Fair Value, Inputs, Level 3 [Member]
Investments, fair value	3,535
Mutual Fund [Member] \| Fair Value, Inputs, Level 1 [Member]
Investments, fair value	3,903
Mutual Fund [Member] \| Fair Value, Inputs, Level 2 [Member]
Investments, fair value	0
Mutual Fund [Member] \| Fair Value, Inputs, Level 3 [Member]
Investments, fair value	$ 0