Note 1 - Description of Business and Significant Accounting Policies (Details Textual)	3 Months Ended		9 Months Ended
	Sep. 30, 2019 $ / shares shares	Sep. 30, 2018 shares	Sep. 30, 2019 $ / shares shares	Sep. 30, 2018 shares	Dec. 31, 2018 $ / shares shares
Number of Wholly-Owned Operating Subsidiaries	5		5
Common Stock, Par or Stated Value Per Share | $ / shares	$ 0.10		$ 0.10		$ 0.10
Common Stock, Shares Authorized	20,000,000		20,000,000		20,000,000
Common Stock, Shares, Issued, Total	7,732,570		7,732,570		7,650,551
Weighted Average Number of Shares Outstanding, Basic and Diluted	7,715,583	7,474,022	7,681,612	7,368,451