Accrued Restructuring Charge (Schedule Of Accrued Liability Associated With Realignment) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Apr. 30, 2014
Restructuring Cost and Reserve [Line Items]
Charges	$ 1,197
Payments	(637)
Accrued liability at April 30, 2014	560
Severance [Member]
Restructuring Cost and Reserve [Line Items]
Charges	414
Payments	(318)
Accrued liability at April 30, 2014	96
Lease Abandonment [Member]
Restructuring Cost and Reserve [Line Items]
Charges	783
Payments	(319)
Accrued liability at April 30, 2014	$ 464