Note 3 - Summary of Significant Accounting Policies - Cash and Cash Equivalents (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Money Market Funds	$ 188,640,417	$ 32,968,833	$ 61,121,678
Demand Deposit Savings Accounts	46,061,819	99,262,744	95,809,411
Commercial Paper	199,360,060	119,980,366	152,447,206
Total cash and cash equivalents as presented on the combined Statement of Assets and Liabilities	$ 434,062,296	$ 252,211,943	$ 309,378,295