Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012
Statement Of Other Comprehensive Income [Abstract]
Net income	$ 6,768	$ 6,619	$ 6,925
Other comprehensive income/(loss), net of tax:
Change in unrealized gains on securities, net of taxes	(5)	166	22
Other comprehensive income/(loss)	(5)	166	22
Comprehensive income/(loss)	$ 6,763	$ 6,785	$ 6,947