Related Party Transactions - Additional information (Detail) (USD $) In Millions, unless otherwise specified	Jul. 31, 2012	Apr. 30, 2012
Related Party Transaction [Line Items]
Payables and accruals, due	$ 2.0	$ 2.0
Receivables, due	$ 1.0	$ 0.9

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Reference 7: http://www.xbrl.org/2003/role/presentationRef

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+ Details

- Definition

Carrying amount as of the balance sheet date of obligations due all related parties.

+ References

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-Publisher FASB

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-Publisher SEC

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+ Details