Stock Options and Share-Based Compensation (Tables)

12 Months Ended

Apr. 30, 2018

Equity [Abstract]

Fair Value of Options Granted Using Black-Scholes Model

The fair value of the options granted as shown below was estimated using the Black-Scholes model with the following assumptions:

	2017			2016
	2008 Plan			2008 Plan
Options granted		45,200			40,200
Weighted average expected stock price volatility		29.17	%		30.45	%
Expected option life		6.25 years			6.25 years
Average risk-free interest rate		2.10	%		1.97	%
Average dividend yield		3.00	%		2.78	%
Estimated fair value of each option	$	5.04		$	3.97

Summary of Stock Option Activity and Weighted Average Exercise Price

Stock option activity and weighted average exercise price are summarized as follows:

	2018					2017					2016
	Number of Shares			Weighted Average Exercise Price		Number of Shares			Weighted Average Exercise Price		Number of Shares			Weighted Average Exercise Price
Outstanding at beginning of year		180,350		$	17.29		185,375		$	14.68		239,575		$	13.24
Granted		—			—		45,200			22.92		40,200			16.92
Canceled		(6,300	)		19.09		(150	)		10.64		(10,400	)		16.37
Exercised		(36,800	)		14.31		(50,075	)		12.72		(84,000	)		11.44
Outstanding at end of year		137,250		$	18.01		180,350		$	17.29		185,375		$	14.68
Exercisable at end of year		79,100		$	16.28		78,650		$	14.22		92,075		$	12.83

Summary of Options Outstanding, Exercisable, and Weighted Average Exercise Prices within Exercise Price Range

The number of options outstanding, exercisable, and their weighted average exercise prices were within the following ranges at April 30, 2018:

	Exercise Price Range
	$8.59-$11.78		$15.85-$23.62
Options outstanding		17,550		119,700
Weighted average exercise price	$	11.35	$	18.98
Weighted average remaining contractual life		4.03 years		6.68 years
Aggregate intrinsic value	$	414,000	$	1,911,000
Options exercisable		17,550		61,550
Weighted average exercise price	$	11.35	$	17.69
Aggregate intrinsic value	$	414,000	$	1,062,000