Condensed Consolidated Statements Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Oct. 31, 2014	Oct. 31, 2013	Oct. 31, 2014	Oct. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 7,671	$ 5,271	$ 16,909	$ 11,926
Other comprehensive income, net of tax:
Change in pension benefits, net of deferred tax of $(84) and $(110), and $(167) and $(220), for the three and six months ended October 31, 2014 and 2013, respectively	132	173	263	345
Total Comprehensive Income	$ 7,803	$ 5,444	$ 17,172	$ 12,271