Note 15 - Related Party Transactions (Details Textual) - Stellartech Research Corporation [Member]	1 Months Ended	12 Months Ended
	Jun. 30, 2006	Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($)
Stock Issued During Period, Shares, New Issues (in shares) | shares		38
Related Party Transaction, Amounts of Transaction | $		$ 205,000	$ 1,051,000
Electricity, Generation [Member]
Development and Manufacturing Agreement, Number of Units	300
Development and Manufacturing Agreement, Number of Units Purchased	855