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falsefalseAs_Of_3_20_2013http://www.sec.gov/CIK0000750199instant2013-03-20T00:00:000001-01-01T00:00:00Unit14Standardhttp://eplweb.com/20130630itemepl05false USDfalsefalse$As_Of_12_31_2008http://www.sec.gov/CIK0000750199instant2008-12-31T00:00:000001-01-01T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 1us-gaap_CommitmentsAndContingenciesDisclosureAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Commitments and Contingencies [Abstract]2false 2epl_NumberOfLeasesBidUponepl_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalselabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4truefalsefalse55falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:decimalItemTypedecimalNumber of leases bid uponNo definition available.false256Number of leases bid upon3false 2epl_AmountPaidOnLeasesAwardedepl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalselabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse15000001.5USD$falsetruefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount paid on leases awardedNo definition available.false2Amount paid on leases awarded4false 2epl_AmountOfLeasesAwardedepl_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse18000001.8falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of leases awardedNo definition available.false2Amount of leases awarded5false 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Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 false2Escrow DepositfalseCommitments and Contingencies (Narrative) (Details) (USD $)HundredThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://eplweb.com/role/DisclosureCommitmentsAndContingenciesNarrativeDetails514