Acquisition Cost Per Share

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- Definition

Additional principal amount of senior notes to be raised

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- Definition

Amount of debt and preferred stock assumed by AES at acquisition

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- Definition

Divestiture Of Business Potential Fees

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- Definition

Quarterly Common Stock Dividend Maximum Limit

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- Definition

Value of divestiture of business

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- Definition

Interest rate stated in the contractual debt agreement.

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- Definition

When presenting a range of maturity dates, the latest date when the outstanding debt instruments are required to be repaid. May be presented in a variety of ways (for example: year only, month and year, day, month and year, and number of years).

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

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the operating cycle if longer, excluding current portion.

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Carrying value as of the balance sheet date of the portion of long-term notes having the highest claim on the assets of the issuer in case of bankruptcy or liquidation, due within one year or the normal operating cycle, if longer. Senior note holders are paid off in full before any payments are made to debt holders having a lesser priority of repayment.

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Proposed Merger with the AES Corporation (Narrative) (Details) (USD $)	0 Months Ended	9 Months Ended				9 Months Ended	3 Months Ended		0 Months Ended
	Apr. 19, 2011	Sep. 30, 2011	Mar. 01, 2011	Sep. 30, 2011 Senior Notes Maturing in September 2011 - 6.875% [Member]	Dec. 31, 2010 Senior Notes Maturing in September 2011 - 6.875% [Member]	Sep. 30, 2011 DP&L [Member] U.S. Government note maturing in February 2061 - 4.20% [Member]	Sep. 30, 2011 DP&L [Member]	Nov. 21, 2006 DP&L [Member]	Apr. 19, 2011 Contract Termination [Member]
Acquisition cost per share	$ 30.00
Value of divestiture of business	$ 3,500,000,000
Amount of debt and preferred stock assumed by AES at acquisition	1,200,000,000
Maximum quarterly common stock dividend per share		0.3325
Senior notes maturing in September 2011				297,400,000	297,400,000
Debt instrument interest percentage			4.20%	6.875%		4.20%
Debt instrument maturity year		2061				February 2061	2026
Additional principal amount of senior notes to be raised		1,250,000,000
Unsecured revolving credit agreement								220,000,000
Loans Payable to Bank, Noncurrent		425,000,000
Divestiture of business potential fees		$ 45,000,000							$ 106,000,000