Goodwill Allocated to DP&L Reporting Unit

No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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-Publisher FASB

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-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

+ Details

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

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-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Impairment

-URI http://asc.fasb.org/extlink&oid=6515133

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- Definition

Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 1

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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 13

-Subparagraph a

-Article 5

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 7

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Fair Value Measurements (Fair Value of Assets and Liabilities Measured on a Nonrecurring Basis) (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended	12 Months Ended		3 Months Ended	12 Months Ended	3 Months Ended
	Oct. 01, 2013	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2013	Jun. 30, 2014	Dec. 31, 2014	Mar. 31, 2015
Carrying Value				$ 2,534.2us-gaap_PropertyPlantAndEquipmentNet		$ 2,517.6us-gaap_PropertyPlantAndEquipmentNet	$ 2,510.6us-gaap_PropertyPlantAndEquipmentNet
Fixed asset impairment		11.5
Goodwill				452.8us-gaap_Goodwill		317.0us-gaap_Goodwill	317.0us-gaap_Goodwill
Goodwill Impairment	306.3us-gaap_GoodwillImpairmentLoss	135.8us-gaap_GoodwillImpairmentLoss
Goodwill Allocated to DP&L Reporting Unit						2.4dpl_GoodwillAllocatedToDpLReportingUnit
Estimate of Fair Value, Fair Value Disclosure [Member]
Goodwill Allocated to DP&L Reporting Unit				306.3
Level 1 [Member]
Goodwill Allocated to DP&L Reporting Unit				623.3
Level 3 [Member]
Goodwill Allocated to DP&L Reporting Unit				317.0
Parent Company [Member]
Goodwill Impairment			1,817.2
DP&L [Member]
Goodwill			623.3	317.0		317.0
Goodwill Impairment				(306.3)
DPLER [Member]
Fair Value							135.8
Goodwill		135.8	135.8	135.8
Goodwill Impairment		135.8			135.8	(135.8)
DPLER [Member] \| Estimate of Fair Value, Fair Value Disclosure [Member]
Carrying Value							135.8
Conesville Unit 4 [Member]
Fixed asset impairment				26.2
Fair Value				0
Conesville Unit 4 [Member] \| Estimate of Fair Value, Fair Value Disclosure [Member]
Carrying Value				26.2
Conesville Unit 4 [Member] \| Level 1 [Member]
Carrying Value				26.2
East Bend Station [Member]
Carrying Value						14.2
Fixed asset impairment		11.5		11.5
Fair Value		2.7		2.7			11.5
East Bend Station [Member] \| Estimate of Fair Value, Fair Value Disclosure [Member]
Carrying Value							14.2
Fair Value						11.5
East Bend Station [Member] \| Level 3 [Member]
Fixed asset impairment						2.7	2.7
DPLER [Member]
Goodwill						135.8
DPLER [Member] \| Estimate of Fair Value, Fair Value Disclosure [Member]
Goodwill						$ 135.8