Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717

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

Leases (Details) - USD ($) $ in Thousands	12 Months Ended
Leases (Details) - USD ($) $ in Thousands	Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2013
Capital Leased Assets
Rent expense under operating leases	$ 1,961	$ 1,424	$ 1,773
Minimum \| Capital Lease Obligations
Capital Leased Assets
Capital lease term (in years)	5 years
Maximum \| Capital Lease Obligations
Capital Leased Assets
Capital lease term (in years)	20 years