Note 19 - Summary of Quarterly Results (Unaudited) - Quarterly Results (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended												12 Months Ended
		Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2017		Jun. 30, 2016		Jun. 30, 2015		Jun. 30, 2014	Jun. 30, 2013
Basic (in dollars per share)		$ 0.03	$ (0.02)	$ 0.08	$ 0.03	$ 0.06	$ 0.02	$ 0.15	$ 0.15	$ 0.07	$ 0.02	$ 0.06	$ 0.06	$ 0.12		$ 0.38		$ 0.21		$ 0.04	$ (0.01)
Diluted (in dollars per share)		$ 0.03	$ (0.02)	$ 0.08	$ 0.03	$ 0.06	$ 0.02	$ 0.15	$ 0.15	$ 0.07	$ 0.02	$ 0.06	$ 0.06	$ 0.12		$ 0.37		$ 0.21		$ 0.04	$ (0.01)
Inter-segment Revenues		$ 83,419	$ 78,156	$ 85,658	$ 84,159	$ 80,844	$ 70,740	$ 84,687	$ 85,925	$ 76,073	$ 68,603	$ 84,715	$ 78,466	$ 331,392	[1]	$ 322,196	[1]	$ 307,857	[1]	$ 299,463	$ 280,790
Gross profit		21,236	18,399	21,407	20,835	19,847	16,549	23,926	23,349	18,981	16,305	20,555	18,608	81,877		83,671		74,449
Net income		$ 696	$ (531)	$ 2,006	$ 829	$ 1,428	$ 522	$ 3,782	$ 3,750	$ 1,643	$ 393	$ 1,588	$ 1,527	$ 3,000		$ 9,482		$ 5,151		$ 930	$ (123)
Maximum [Member]
High (in dollars per share)		$ 10.21	$ 10.68	$ 11.23	$ 11.64	$ 13.45	$ 12.22	$ 12.80	$ 10.48	$ 10.24	$ 9.17	$ 7.70	$ 8.49	$ 10.21		$ 13.45		$ 10.24
Minimum [Member]
High (in dollars per share)		8.26	$ 8.31	$ 8.12	$ 9.41	10.29	$ 9.85	$ 7.89	$ 8.33	8.02	$ 5.84	$ 5.61	$ 6	8.26		10.29		8.02
Fiscal Year [Member]
Basic (in dollars per share)														0.12		0.38		0.21	[2]
Diluted (in dollars per share)	[2]													$ 0.12		$ 0.37		$ 0.21
Inter-segment Revenues														$ 331,392		$ 322,196		$ 307,857
Gross profit														81,877		83,671		74,449
Net income														$ 3,000		$ 9,482		$ 5,151
Fiscal Year [Member] | Maximum [Member]
High (in dollars per share)		11.64				13.45				10.24				$ 11.64		$ 13.45		$ 10.24
Fiscal Year [Member] | Minimum [Member]
High (in dollars per share)		$ 8.12				$ 7.89				$ 5.61				$ 8.12		$ 7.89		$ 5.61

[1] Net sales are attributed to geographic areas based upon the location of the operation making the sale.

[2] The total of the earnings per share for each of the four quarters does not equal the total earnings per share for the full year because the calculations are based on the average shares outstanding during each of the individual periods.