Note 21 - Commitments and Contingencies (Details Textual) - USD ($)	3 Months Ended	12 Months Ended		23 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Feb. 28, 2018
Payment for Blockchain Technology Based Applications Development Costs		$ 160,000	$ 3,738,000	$ 3,880,000
Subsequent Event [Member]
Payment for Blockchain Technology Based Applications Development Costs	$ 300,000
Contract to Develop Blockchain Technology Based Applications [Member]
Application Development Contracts, Contract Amount		$ 4,930,000		$ 4,930,000	$ 4,500,000