Note 1 - Description of Business and Significant Accounting Policies (Details Textual) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Common Stock, Par or Stated Value Per Share	$ 0.10		$ 0.10		$ 0.10
Common Stock, Shares Authorized	20,000,000		20,000,000		20,000,000
Common Stock, Shares, Issued, Total	7,453,287		7,453,287		7,310,939
Weighted Average Number of Shares Outstanding, Basic and Diluted	7,389,200	5,596,489	7,346,064	5,579,493
Common Stock, Shares, Outstanding, Ending Balance	7,453,287		7,453,287		7,310,939