Contractual Obligations, Commercial Commitments and Contingencies (Narative) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended		9 Months Ended							9 Months Ended													9 Months Ended
	Sep. 30, 2014 T	Sep. 30, 2013	Sep. 30, 2014 DP&L [Member] T	Dec. 31, 2013 DP&L [Member]	Sep. 30, 2014 Electric Generation Company [Member]	Sep. 30, 2014 DPLER [Member]	Sep. 30, 2013 DPLE [Member]	Sep. 30, 2014 MC Squared [Member]	Sep. 30, 2014 Beckjord Unit 6 [Member] DP&L [Member]	Sep. 30, 2014 Debt Obligation on 4.9% Equity Ownership [Member]	Sep. 30, 2014 Debt Obligation on 4.9% Equity Ownership [Member] DP&L [Member]	Sep. 30, 2014 Pollution Control Series Maturing in January 2028 - 4.70% [Member]	Sep. 30, 2014 Pollution Control Series Maturing in January 2028 - 4.70% [Member] DP&L [Member]	Sep. 30, 2014 Pollution Control Series Maturing in January 2034 - 4.80% [Member]	Sep. 30, 2014 Pollution Control Series Maturing in January 2034 - 4.80% [Member] DP&L [Member]	Sep. 30, 2014 Pollution Control Series Maturing in September 2036 - 4.80% [Member]	Sep. 30, 2014 Pollution Control Series Maturing in September 2036 - 4.80% [Member] DP&L [Member]	Sep. 30, 2014 U.S. Government note maturing in February 2061 - 4.20% [Member]	Sep. 30, 2014 U.S. Government note maturing in February 2061 - 4.20% [Member] DP&L [Member]	Sep. 30, 2014 Note to DPL Capital Trust II Maturing in September 2031 - 8.125% [Member]	Sep. 30, 2014 Senior Unsecured Notes at 6.50% maturing on October 15, 2016 [Member]	Sep. 30, 2014 Ten Year Senior Unsecured Notes at 7.25% maturing at October 15, 2021 [Member]	Sep. 30, 2014 CO2 [Member]	Sep. 30, 2014 CO2 [Member] DP&L [Member]	Sep. 30, 2014 Interim goals[Member] lb	Sep. 30, 2014 Interim goals[Member] DP&L [Member] lb	Sep. 30, 2014 Final goals[Member] lb	Sep. 30, 2014 Final goals[Member] DP&L [Member] lb
Public Utility, Property, Plant and Equipment [Line Items]
Third party guarantees	$ 19.0					$ 2.0	$ 16.8	$ 0.2
Due to third parties, current	0.4
Equity ownership interest			4.90%							4.90%
Equity ownership interest aggregate cost										76.0	76.0
Debt obligation					1,550.1
Long Term Debt Date Range Equity Ownership, Start			2018							2018
Long Term Debt Date Range Equity Ownership, End			2040							2040
Debt instrument interest percentage												4.70%	4.70%	4.80%	4.80%	4.80%	4.80%	4.20%	4.20%	8.125%	6.50%	7.25%
Environmental reserves	$ 0.9	$ 1.1	$ 0.9	$ 1.1
Percentage of energy generated by coal	99.00%		99.00%
Emission Reductions																							30.00%	30.00%
Emission Reductions Ohio																							28	28
Annual CO2 emissions generation at stations, in tons	14,000,000		14,000,000
CO2 tons per megawatt-hour for USEPA standard on new EGUs																									1,452,000	1,452,000	1,338,000	1,338,000
Ownership (%)									50.00%