Note 1 - Summary of Significant Accounting Policies (Details Textual)	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)
Number of Subsidiaries	4		4
Income Tax Expense (Benefit)	$ 2,635,576	$ 2,153,144	$ 5,025,022	$ 4,172,167
Accounting Standards Update 2016-09 [Member]
Income Tax Expense (Benefit)	$ (90,000)		$ (623,000)