Note 4 - Income Taxes (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Effective Income Tax Rate Reconciliation, Percent, Total	17.20%	16.60%	18.70%	11.60%
Increase Decrease In Income Tax Expense From Changing Software Development Tax Depreciation Method		$ (308,000)		$ (308,000)
Increase (Decrease) in Income Tax Expense from Exercise of Options and Dividends Paid to Non-vested Shareholders	$ (459,000)			247,000
Income Tax Expense (Benefit) Related to Recapitalization				$ (1,100,000)
Increase (Decrease) in Income Tax Expense from Non-deductible Recapitalization Expenses			$ 154,000
Foreign Tax Authority [Member] | Canada Revenue Agency [Member]
Increase (Decrease) in Income Tax Expense from Withholding on Unrepatriated Foreign Earnings	$ 90,000		$ 90,000