Summary of Significant Accounting Policies (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Jan. 31, 2015	Apr. 30, 2014	Apr. 30, 2013
Balance end of year	$ (610)us-gaap_DerivativeLiabilitiesNoncurrent	$ (2,011)us-gaap_DerivativeLiabilitiesNoncurrent	$ (1,046)us-gaap_DerivativeLiabilitiesNoncurrent
Fair Value, Inputs, Level 3 [Member]
Balance beginning of year	(2,011)	(1,046)	(555)
Transfers to (from) Level 3	0	0	0
Total gains (losses) included in earnings	1,401	(965)	(74)
Issuances	0	0	(417)
Balance end of year		$ (2,011)	$ (1,046)

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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

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This item represents the amount of the total realized and unrealized gains or losses for the period which are included in the statement of income (or changes in net assets); the fair value of which assets and liabilities was or is measured on a recurring basis using significant unobservable inputs (Level 3).

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Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy.

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