Production Plan Capacity

No definition available.

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- Definition

SCR and FGD Equipment Installed and In Service

+ References

No definition available.

+ Details

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- Definition

The period end amount owned by the reporting utility of a jointly owned utility plant in service.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 360

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 10.C)

-URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 10

-Section C

+ Details

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- Definition

The period end amount of construction work in progress at a jointly owned electricity generation plant.

+ References

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The period end amount of accumulated depreciation in a jointly owned electricity generation plant.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

+ References

+ Details

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Data Type:	num:percentItemType
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- Details

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- Details

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Ownership of Coal-fired Facilities (Ownership Interests) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended	3 Months Ended		12 Months Ended
	Dec. 31, 2013 MW	Mar. 31, 2014 MW	Mar. 31, 2015 MW	Dec. 31, 2014 MW
Construction Work in Process			24.0	25.0
Conesville Unit 4 [Member]
Production Capacity (MW)	129
East Bend Station [Member]
Production Capacity (MW)		186
DP&L Share [Member] \| Conesville Unit 4 [Member]
Ownership (%)			16.50%	16.50%
Production Capacity (MW)			129	129
DP&L Share [Member] \| Killen Station [Member]
Ownership (%)			67.00%	67.00%
Production Capacity (MW)			402	402
DP&L Share [Member] \| Miami Fort Units 7 and 8 [Member]
Ownership (%)			36.00%	36.00%
Production Capacity (MW)			368	368
DP&L Share [Member] \| Stuart Station [Member]
Ownership (%)			35.00%	35.00%
Production Capacity (MW)			808	808
DP&L Share [Member] \| Zimmer Station [Member]
Ownership (%)			28.10%	28.10%
Production Capacity (MW)			371	371
DP&L Share [Member] \| Total Jointly-owned Stations [Member]
Production Capacity (MW)			2,078	2,078
DP&L Investment [Member] \| Conesville Unit 4 [Member]
Gross Plant In Service			25	24
Accumulated Depreciation			2	2
Construction Work in Process			1.0	1.0
SCR and FGD Equipment Installed and In Service			Yes	Yes
DP&L Investment [Member] \| Killen Station [Member]
Gross Plant In Service			308	308
Accumulated Depreciation			22	19
Construction Work in Process			4.0	2.0
SCR and FGD Equipment Installed and In Service			Yes	Yes
DP&L Investment [Member] \| Miami Fort Units 7 and 8 [Member]
Gross Plant In Service			214	214
Accumulated Depreciation			26	23
Construction Work in Process			3.0	2.0
SCR and FGD Equipment Installed and In Service			Yes	Yes
DP&L Investment [Member] \| Stuart Station [Member]
Gross Plant In Service			220	219
Accumulated Depreciation			17	16
Construction Work in Process			12.0	14.0
SCR and FGD Equipment Installed and In Service			Yes	Yes
DP&L Investment [Member] \| Zimmer Station [Member]
Gross Plant In Service			185	182
Accumulated Depreciation			37	35
Construction Work in Process			4.0	6.0
SCR and FGD Equipment Installed and In Service			Yes	Yes
DP&L Investment [Member] \| Total Jointly-owned Stations [Member]
Gross Plant In Service			994	989
Accumulated Depreciation			110	101
Construction Work in Process			24.0	25.0
DP&L Investment [Member] \| Transmission (At Varying Percentages) [Member]
Gross Plant In Service			42	42
Accumulated Depreciation			6	6