Note 2 - Accounts Receivable - Allowance for Doubtful Accounts (Details) - USD ($)	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Allowance for credit losses, beginning of period	$ 72,045	$ 73,728
Current period provision	16,775	(3,671)
Write-off	(6,752)	0
Allowance for credit losses, end of period	$ 82,068	$ 70,057