Standard set by USEPA on CO2 emmisions on new electric generating units (EGUs).

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Due to third parties current.

+ References

No definition available.

+ Details

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- Definition

Emission Reductions in S02 and NOx

+ References

No definition available.

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- Definition

Emission Reductions in S02 and NOx in Ohio

+ References

No definition available.

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- Definition

Long Term Debt Date Range Equity Ownership, End

+ References

No definition available.

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- Definition

Long Term Debt Date Range Equity Ownership, Start

+ References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	dpl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 12

-Article 5

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Period Type:	instant

- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section H

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Period Type:	instant

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Contractual Obligations, Commercial Commitments and Contingencies (Narative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Public Utility, Property, Plant and Equipment [Line Items]
Third party guarantees	$ 20.5
Due to third parties, current	2.2dpl_DueToThirdPartiesCurrent
Environmental reserves	0.8	0.8
DP&L [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Equity ownership interest	4.90%
Long Term Debt Date Range Equity Ownership, Start	2018
Long Term Debt Date Range Equity Ownership, End	2040
Environmental reserves	0.8	0.8
Electric Generation Company [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Debt obligation	1,519.3
DPLER [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Third party guarantees	2.0
DPLE [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Third party guarantees	18.3
MC Squared [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Third party guarantees	0.2
Debt Obligation on 4.9% Equity Ownership [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Equity ownership interest	4.90%
Equity ownership interest aggregate cost	74.4
Long Term Debt Date Range Equity Ownership, Start	2018
Long Term Debt Date Range Equity Ownership, End	2040
Debt Obligation on 4.9% Equity Ownership [Member] \| DP&L [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Equity ownership interest aggregate cost	$ 74.4
Pollution Control Series Maturing in January 2028 - 4.70% [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Debt instrument interest percentage	4.70%
Pollution Control Series Maturing in January 2028 - 4.70% [Member] \| DP&L [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Debt instrument interest percentage	4.70%
Pollution Control Series Maturing in January 2034 - 4.80% [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Debt instrument interest percentage	4.80%
Pollution Control Series Maturing in January 2034 - 4.80% [Member] \| DP&L [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Debt instrument interest percentage	4.80%
Pollution Control Series Maturing in September 2036 - 4.80% [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Debt instrument interest percentage	4.80%
Pollution Control Series Maturing in September 2036 - 4.80% [Member] \| DP&L [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Debt instrument interest percentage	4.80%
U.S. Government note maturing in February 2061 - 4.20% [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Debt instrument interest percentage	4.20%
U.S. Government note maturing in February 2061 - 4.20% [Member] \| DP&L [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Debt instrument interest percentage	4.20%
Note to DPL Capital Trust II Maturing in September 2031 - 8.125% [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Debt instrument interest percentage	8.125%
Senior Unsecured Notes at 6.50% maturing on October 15, 2016 [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Debt instrument interest percentage	6.50%
Ten Year Senior Unsecured Notes at 7.25% maturing at October 15, 2021 [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Debt instrument interest percentage	7.25%
CO2 [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Emission Reductions	30.00%
Emission Reductions Ohio	28
CO2 [Member] \| DP&L [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Emission Reductions	30.00%
Emission Reductions Ohio	28
Interim goals[Member]
Public Utility, Property, Plant and Equipment [Line Items]
CO2 tons per megawatt-hour for USEPA standard on new EGUs	1,452,000
Interim goals[Member] \| DP&L [Member]
Public Utility, Property, Plant and Equipment [Line Items]
CO2 tons per megawatt-hour for USEPA standard on new EGUs	1,452,000
Final goals[Member]
Public Utility, Property, Plant and Equipment [Line Items]
CO2 tons per megawatt-hour for USEPA standard on new EGUs	1,338,000
Final goals[Member] \| DP&L [Member]
Public Utility, Property, Plant and Equipment [Line Items]
CO2 tons per megawatt-hour for USEPA standard on new EGUs	1,338,000