Note I - Stock Based Compensation (Details) - Options Exercised (USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended
	Jan. 31, 2014	Jan. 31, 2013
Options Exercised [Abstract]
Options Exercised (in Shares)	30,500	28,500
Cash Received from Option Exercises	$ 719	$ 665
Intrinsic Value of Options Exercised	$ 563	$ 603