SIGNIFICANT ACCOUNTING POLICIES - Transportation (Details)	12 Months Ended
Dec. 31, 2019 agreement
Transportation
Number of agreement types common in the industry	2

Represents the number of agreement types common in the industry.

No definition available.

Name:	erf_NumberOfCommonIndustryAgreementTypes
Namespace Prefix:	erf_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration