Consolidated Statements of Operations (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Jul. 31, 2013	Jul. 31, 2012
Income Statement [Abstract]
Income (loss) from discontinued operations, income tax provision	$ 0	$ 0
Loss on disposal of discontinued operations, income tax provision	$ 0	$ 0

Income tax expense or benefit attributable to Income or Loss from discontinued operations during the phase-out period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

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

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-Name Accounting Standards Codification

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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