Note K - Stock-Based Compensation Plans (Tables)

12 Months Ended

Apr. 30, 2014

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock Option Plan Comparison [Table Text Block]

	1997 Plan	2007 Plan
Minimum exercise price as a percentage of fair market value at date of grant	100%	100%
Last expiration date for outstanding options	July 2, 2017	May 6, 2023
Shares available for grant at April 30, 2014	-	367,500

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	April 30, 2014	April 30, 2013	April 30, 2012
Expected terms (years)	5.0	5.0	5.0
Risk-free interest rate	0.67%	0.78%	1.48%
Volatility	50%	50%	50%
Dividend yield	-	-	-

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

	Number of Shares			Exercise Price per Share			Proceeds on Exercise			Weighted Average Exercise Price per Share
							(in thousands)
Outstanding at April 30, 2011		1,133,147		$6.59	to	$24.47	$	21,897		$	19.32
Granted		73,750		$24.69	to	$45.72		2,355			31.93
Exercised		(88,647	)	$6.59	to	$24.69		(1,371	)		15.46
Outstanding at April 30, 2012		1,118,250		$11.83	to	$45.72	$	22,881		$	20.46
Granted		40,000		$44.14	to	$45.46		1,801			45.02
Exercised		(35,750	)	$11.83	to	$23.34		(790	)		22.13
Outstanding at April 30, 2013		1,122,500		$11.90	to	$45.72	$	23,892		$	21.28
Granted		25,000		$44.52	to	$46.44		1,122			44.90
Exercised		(30,500	)	$23.34	to	$23.75		(720	)		23.58
Outstanding at April 30, 2014		1,117,000		$11.90	to	$46.44	$	24,294		$	21.75

Schedule of Share-based Compensation, Stock Options, Exercises [Table Text Block]

	Twelve Months Ended April 30,
(Dollars in thousands)	2014		2013		2012
Options Exercised		30,500		35,750		88,647
Cash Received from Option Exercises	$	720	$	790	$	1,370
Intrinsic Value of Options Exercised	$	563	$	811	$	1,520

Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]

	Number of Shares		Weighted Average Grant Date Fair Value
Unvested shares at April 30, 2013		23,500	$	23.66
Shares granted		-		-
Shares vested		3,500		19.06
Unvested shares at April 30, 2014		20,000	$	24.47