7. EQUITY COMPENSATION PLANS (Details 3) (USD $)	12 Months Ended
Apr. 30, 2013	Apr. 30, 2012	Apr. 30, 2011
Share based compensation	$ 3,435,000	$ 2,769,000	$ 2,837,000
Stock Options
Share based compensation	3,039,000	2,673,000	2,598,000
Restricted stock awards
Share based compensation			185,000
Employee stock purchase plan
Share based compensation	$ 396,000	$ 96,000	$ 54,000

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration