Asset Retirement Obligations (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Sep. 30, 2013	Dec. 31, 2013
Asset Retirement Obligations [Abstract]
Revision to Asset Retirement Obligation of Non Operated Interests		$ 20.8
Loss on Abandonment Activities of Non Operated Interests	$ 22.6	$ 20.8

Revision to Asset Retirement Obligation of Non Operated Interests

No definition available.

Name:	epl_RevisionToAssetRetirementObligationOfNonOperatedInterests
Namespace Prefix:	epl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration