Revenues from External Customers and Long-Lived Assets, by Geographical Areas -Supplemental information (Detail)	12 Months Ended
May 31, 2016
Segment Reporting [Abstract]
Minimum percentage of revenue accounted for major customer	10.00%

Minimum percentage of revenue accounted for major customer.

No definition available.

Name:	elrc_MinimumPercentageOfRevenueAccountedForMajorCustomer
Namespace Prefix:	elrc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration