Name:	ep_OilAndGasSuccessfulEffortsMethodPropertyAndEquipmentWorkInProgressBeforeAccumulatedDepreciationDepletionAmortizationAndImpairment
Namespace Prefix:	ep_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount of accumulated depreciation, depletion, amortization and impairment of oil and gas property carried under the successful effort method.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 932
-SubTopic 360
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478810/932-360-50-1

Name:	us-gaap_OilAndGasPropertySuccessfulEffortMethodAccumulatedDepreciationDepletionAmortizationAndImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount, before accumulated depreciation, depletion, amortization, and impairment, of oil and gas properties accounted for under successful efforts method.

Name:	us-gaap_OilAndGasPropertySuccessfulEffortMethodGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount, after accumulated depreciation, depletion, amortization, and impairment, of oil and gas properties accounted for under successful efforts method.

Name:	us-gaap_OilAndGasPropertySuccessfulEffortMethodNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

Name:	us-gaap_PropertyPlantAndEquipmentAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount, before accumulated depreciation, depletion, amortization, and impairment, of oil and gas properties with proved reserve accounted for under successful efforts method.

Name:	us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount, before accumulated depreciation, depletion, amortization, and impairment, of oil and gas properties with unproved reserve accounted for under successful efforts method.