Note 8 - Stockholders' Equity - Summary of Shares to be Issued (Details) - shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Shares-to-be-issued, outstanding (in shares)	2,066,343	2,440,878
Granted in current period (in shares)	108,148	33,238
Issued in current period (in shares)	0	(65,965)
Shares-to be issued outstanding (in shares)	2,174,491	2,408,151