Employee Incentive Plans (Details) (Deferred Bonus [Member], USD $)	12 Months Ended
Apr. 30, 2012	Apr. 30, 2011
Long Term [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Incentive Plan Award	$ 0	$ 0
Short Term [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Incentive Plan Award	$ 0	$ 0

Amount of commitment made to pay deferred cash remuneration.

No definition available.

Name:	us-gaap_DeferredCompensationArrangementWithIndividualCashAwardsGrantedAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration