Related Party Transactions Related Party Transactions - Additional Information (Details) (USD $) In Thousands, unless otherwise specified	Apr. 30, 2013
Related Party Transaction [Line Items]
Accounts receivable due from related party	$ 76,880

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 2: http://www.xbrl.org/2003/role/presentationRef

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

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Reference 8: http://www.xbrl.org/2003/role/presentationRef

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+ Details