Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2013
Statement Of Other Comprehensive Income [Abstract]
Net income	$ 7,292	$ 6,768	$ 6,619
Other comprehensive income/(loss), net of tax:
Change in unrealized gains on securities, net of taxes	(141)	(5)	166
Other comprehensive income/(loss)	(141)	(5)	166
Comprehensive income/(loss)	$ 7,151	$ 6,763	$ 6,785