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Allocation to Total Purchase Price (Detail) (USD $) In Thousands, unless otherwise specified	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012	Aug. 14, 2013 Taylor Manufacturing Systems, USA, LLC
Business Acquisition [Line Items]
Current assets				$ 130
Goodwill	13,819	12,601	12,601	1,218
Current technology				472
Total Assets Acquired				1,820
Current liabilities				(13)
Net Assets Acquired				$ 1,807