Commitments (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Apr. 30, 2013 employee
Commitments [Abstract]
Minimum aggregate base compensation per year exclusive of bonuses for executive officer	$ 660
Number of other key employees compensation agreements were entered into with	11

Number Of Key Employees Compensation Agreements Were Entered Into

No definition available.

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Period Type:	duration