Condensed Consolidated Statements Of Income (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Oct. 31, 2014	Oct. 31, 2013	Oct. 31, 2014	Oct. 31, 2013
Income Statement [Abstract]
Net sales	$ 217,693	$ 190,532	$ 429,610	$ 368,627
Cost of sales and distribution	180,712	158,258	355,515	302,638
Gross Profit	36,981	32,274	74,095	65,989
Selling and marketing expenses	16,296	15,867	31,811	30,351
General and administrative expenses	8,245	7,590	16,656	15,991
Restructuring charges, net	0	31	3	113
Insurance proceeds	0	0	0	(94)
Operating Income	12,440	8,786	25,625	19,628
Interest expense	150	186	314	372
Other income	(32)	(31)	(65)	(57)
Income Before Income Taxes	12,322	8,631	25,376	19,313
Income tax expense	4,651	3,360	8,467	7,387
Net Income	$ 7,671	$ 5,271	$ 16,909	$ 11,926
Weighted Average Shares Outstanding
Basic (shares)	15,672,198	15,230,584	15,602,150	15,089,995
Diluted (shares)	15,960,236	15,581,605	15,864,560	15,479,180
Net earnings per share
Basic (usd per share)	$ 0.49	$ 0.35	$ 1.08	$ 0.79
Diluted (usd per share)	$ 0.48	$ 0.34	$ 1.07	$ 0.77