SIGNIFICANT ACCOUNTING POLICIES - Oil and Natural Gas Properties (Details)	Dec. 31, 2019
Oil and Natural Gas Properties
Discount rate applied to estimated future net cash flows from proved oil and gas reserves (as a percent)	10.00%

Represents the discount rate applied to estimated future net cash flows from proved oil and gas reserves.

No definition available.

Name:	erf_DiscountRateForEstimatedFutureNetCashFlowsFromProvedOilAndGasReserves
Namespace Prefix:	erf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant