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An agreement under which a supplier commits to supply a specified amount of coal over a specified period, and DP&L commits to purchase the coal supplied over the specified period.

No definition available.

Name:	dpl_CoalSupplyAgreement
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Coal Supply Failure By Suppliers

No definition available.

Name:	dpl_CoalSupplyFailureBySuppliers
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Balance Type:	na
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This item represents the amount of total guarantees provided to third parties for future financial or performance assurance. The guarantees are provided to enhance the creditworthiness attributed DPL's subsidiaries, DPLE and DPLER, on a stand-alone basis. Any, against the loss of value in the underlying assets in the security which were considered and relied upon as one of the potential factors in reaching a conclusion that the available-for-sale investments are not other-than -temporarily impaired.

No definition available.

Name:	dpl_DisclosureOtherThirdPartyGuaranteesAmount
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Due to third parties current.

No definition available.

Name:	dpl_DueToThirdPartiesCurrent
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Emission Reductions in S02 and NOx

No definition available.

Name:	dpl_EmissionReductions
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Long Term Debt Date Range Equity Ownership, End

No definition available.

Name:	dpl_LongTermDebtDateRangeEquityOwnershipEnd
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Long Term Debt Date Range Equity Ownership, Start

No definition available.

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Number of Auxiliary Boilers

No definition available.

Name:	dpl_NumberOfAuxiliaryBoilers
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Period Type:	duration

The number of diesel electric generating engines that are impacted by the National Emissions Standards for Hazardous Air Pollutants, a regulatory standard issued by the EPA.

No definition available.

Name:	dpl_NumberOfDieselElectricGeneratingEngines
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The number of emergency black start engines that are impacted by the National Emissions Standards for Hazardous Air Pollutants, a regulatory standard issued by the EPA.

No definition available.

Name:	dpl_NumberOfEmergencyBlackStartEngines
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Period Type:	duration

No definition available.

Name:	dpl_NumberOfTonsOfCo2EmittedPerYearIncludingElectricGeneratingUnits
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Data Type:	num:massItemType
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Percentage ownership in a coal-fired power plant or electric generating unit

No definition available.

Name:	dpl_PercentageOfCoalFirePowerPlantHoldings
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The percentage of total electric energy generated from coal sources.

No definition available.

Name:	dpl_PercentageOfEnergyGeneratedByCoal
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Period Type:	duration

The noncontrolling equity interest in an electric generation company, accounted for under the cost method of accounting.

No definition available.

Name:	dpl_PublicUtilitiesEquityInterestCostMethodPercentage
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Data Type:	num:percentItemType
Balance Type:	na
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The amount of estimated penalties per day collected by a regulating authority for each environmental violation.

No definition available.

Name:	dpl_ReliefAndCivilPenalties
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Balance Type:	debit
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Interest rate stated in the contractual debt agreement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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This element represents the aggregate cost of investments accounted for under the equity method of accounting.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

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The amount of interest income and other income recognized during the period. Included in this element is interest derived from investments in debt securities, cash and cash equivalents, and other investments which reflect the time value of money or transactions in which the payments are for the use or forbearance of money and other income from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business).

No definition available.

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Carrying amount as of the balance sheet date of reserves for the costs of settling insured claims and costs incurred in the claims settlement process attributable to asbestos and environmental claims, net of estimated reinsurance recoveries.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims. This includes an estimate for claims which have been incurred but not reported. Claim adjustment expenses represent the costs estimated to be incurred in the settlement of unpaid claims.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher AICPA

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section 50

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-Subparagraph (a)

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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 17, 18, 19, 20

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-Publisher SEC

-Name Financial Reporting Release (FRR)

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-Name Regulation S-X (SX)

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-Name Statement of Financial Accounting Standard (FAS)

-Number 113

-Paragraph 21, 22, 23, 24, 25

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year or the normal operating cycle, if longer plus capital lease obligations due to be paid more than one year after the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Publisher SEC

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

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Current year reclassification, impairment, donation, or other change to long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

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