Schedule II (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2013
Valuation and Qualifying Accounts [Abstract]
Valuation Allowances and Reserves, Balance	$ 21,515	$ 24,937	$ 19,176	$ 54,613
Valuation Allowances and Reserves, Charged to Cost and Expense	3,207	6,788	12,467
Valuation Allowances and Reserves, Charged to Other Accounts	0	0	0
Valuation Allowances and Reserves, Deductions	$ (6,629)	$ (1,027)	$ (47,904)

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 09
-Article 12

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Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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