Note 2 - Basis of Presentation (Details Textual) - USD ($)	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Operating Lease, Liability, Total	$ 1,503,737
Deferred Income Tax Assets, Net, Total	$ 1,100,714		$ 1,179,454
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset		$ 1,400,855
Operating Lease, Liability, Total		1,527,019
Deferred Income Tax Assets, Net, Total		34,717
Accounting Standards Update 2016-02 [Member] | Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption		$ 91,447