Name:	EP_PurchasePrice
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The element represents royalty suspense.

No definition available.

Name:	EP_RoyaltySuspense
Namespace Prefix:	EP_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The element represents vehicles gross.

No definition available.

Name:	EP_VehiclesGross
Namespace Prefix:	EP_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Period Type:	instant

Carrying amount of an asset that is legally restricted for purposes of settling an asset retirement obligation.

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-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Oil and gas properties, net of depletion, carried under the full cost method.

No definition available.