Note 1 - Summary of Significant Accounting Policies (Details Textual)	3 Months Ended		12 Months Ended
	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Number of Operating Segments	6
Number of Reportable Segments	1
Incremental Costs of Obtaining a Contract, Deferred During Period	$ 1,600,000	$ 868,000
Capitalized Contract Cost, Net, Noncurrent	4,896,000		$ 4,204,000
Asset Impairment Charges, Total	0		0
Goodwill, Ending Balance	57,746,000		57,935,000
Sales and Excise Tax Payable			$ 775,000
Sales and Excise Tax Expense	$ 50,000
Canadian Subsidiary [Member]
Number of Customers	1
Goodwill, Ending Balance	$ 2,000,000
Customer Concentration Risk [Member] | Canadian Subsidiary [Member] | Revenue from Contract with Customer Benchmark [Member]
Concentration Risk, Percentage	56.50%
Selling, General and Administrative Expenses [Member]
Capitalized Contract Cost, Impairment Loss	$ 1,000	$ 21,000
Minimum [Member]
Capitalized Contract Cost, Amortization Period (Year)	3 years
Maximum [Member]
Capitalized Contract Cost, Amortization Period (Year)	5 years