Earnings (Loss) Per Share (Schedule Of Earnings (Loss) Per Share, Basic And Diluted) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Apr. 30, 2014	Jan. 31, 2014	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2013	Oct. 31, 2012	Jul. 31, 2012	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012
Earnings (Loss) Per Share [Abstract]
Net income (loss)	$ 5,634	$ 2,901	$ 5,271	$ 6,655	$ 5,190	$ 2,057	$ 1,950	$ 561	$ 20,461	$ 9,758	$ (20,786)
Denominator for basic earnings (loss) per common share - weighted-average shares									15,299	14,563	14,344
Stock options and restricted stock units									354	270	0
Denominator for diluted earnings (loss) per common share - weighted-average shares and assumed conversions									15,653	14,833	14,344
Basic	$ 0.36	$ 0.19	$ 0.35	$ 0.45	$ 0.36	$ 0.14	$ 0.13	$ 0.04	$ 1.34	$ 0.67	$ (1.45)
Diluted	$ 0.36	$ 0.18	$ 0.34	$ 0.43	$ 0.35	$ 0.14	$ 0.13	$ 0.04	$ 1.31	$ 0.66	$ (1.45)