Basis of Presentation (Details)	Jun. 30, 2015
Basis of Presentation [Abstract]
Percentage of ownership in entities for accounting under equity method, minimum (in hundredths)	20.00%

Represents the minimum percentage of ownership in entities for accounting under equity method.

No definition available.

Name:	useg_MinimumPercentageOfOwnershipInEntitiesForAccountingUnderEquityMethod
Namespace Prefix:	useg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant