Supplementary Quarterly Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	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, 2016	Jun. 30, 2015	Jun. 30, 2014
Supplementary Quarterly Financial Information [Abstract]
Net sales	$ 122,764	$ 125,401	$ 125,410	$ 126,531	$ 121,323	$ 122,529	$ 114,386	$ 108,666	$ 500,106	$ 466,904	$ 438,543
Gross margin	29,430	28,716	27,684	27,869	27,579	29,667	27,094	25,520	113,699	109,860	100,263
Litigation Settlement, Expense		2,030	250			250			(2,280)	(250)	6,250
Net income (1)	$ 6,164	$ 6,944	$ 5,366	$ 5,763	$ 5,780	$ 6,956	$ 4,685	$ 4,878	$ 24,237	$ 22,299	$ 14,990
Earnings per share: Basic	$ 0.80	$ 0.91	$ 0.71	$ 0.77	$ 0.77	$ 0.94	$ 0.63	$ 0.66	$ 3.19	$ 3.00	$ 2.07
Earnings per share: Diluted	$ 0.79	$ 0.89	$ 0.69	$ 0.75	$ 0.74	$ 0.90	$ 0.61	$ 0.64	$ 3.12	$ 2.89	$ 2.00