Intangible Assets (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization expense	$ 1,538	$ 1,538	$ 2,115
Archive And eDiscovery [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization expense	$ 300	$ 300	$ 600