Share-Based Compensation (Information About Stock Options Activity)(Details) (USD $)	11 Months Ended
Nov. 27, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares that vested during the period	$ 1,000,000
Weighted average period to recognize compensation expense (in years)	0 years
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of share-based compensation award exercised during the period	700,000
Proceeds from share-based compensation award exercised during the period	1,600,000
Excess tax benefit from proceeds of share-based compensation award exercised	200,000
Weighted average period to recognize compensation expense (in years)	0 months
DP&L [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of share-based compensation award exercised during the period	700,000
Proceeds from share-based compensation award exercised during the period	1,600,000
Excess tax benefit from proceeds of share-based compensation award exercised	$ 200,000
Weighted average period to recognize compensation expense (in years)	0 months

Fair value of shares that vested during the period

No definition available.

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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (j)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

+ References

+ Details

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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