Pension and Postretirement Benefits (Effect of Change in Health Care Cost Trend Rate) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Service cost plus interest cost, One-percent increase	$ 0.1
Benefit obligation, One-percent increase	1.0
Benefit obligation, One-percent decrease	(0.9)
DP&L [Member]
Service cost plus interest cost, One-percent increase	0.1
Benefit obligation, One-percent increase	1.0
Benefit obligation, One-percent decrease	$ (0.9)

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (m)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

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