Note K - Stock-Based Compensation Plans (Details) - Options Exercised (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012
Options Exercised [Abstract]
Options Exercised (in Shares)	30,500	35,750	88,647
Cash Received from Option Exercises	$ 720	$ 790	$ 1,371
Intrinsic Value of Options Exercised	$ 563	$ 811	$ 1,520