Note 4 - Income Taxes (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2020
Effective Income Tax Rate Reconciliation, Percent, Total	25.30%	20.50%
Effective Income Tax Rate Change, Share-based Compensation	$ 456,000
Social Security Tax Payable, Current	$ 656,000		$ 1,300,000