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Note 16 - Subsequent Events (Details Textual) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended
	May 01, 2019	Apr. 18, 2019	Mar. 31, 2019	Mar. 31, 2018
Common Stock, Dividends, Per Share, Declared			$ 0.075	$ 0.05
Subsequent Event [Member]
Common Stock, Dividends, Per Share, Declared		$ 0.075
Subsequent Event [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 10.0
Proceeds from Lines of Credit, Total	$ 5.3
Subsequent Event [Member] \| Revolving Credit Facility [Member] \| Prime Rate [Member]
Debt Instrument, Basis Spread on Variable Rate	(0.40%)
Subsequent Event [Member] \| Term Note [Member]
Debt Instrument, Face Amount	$ 10.0
Debt Instrument, Interest Rate, Stated Percentage	4.70%