Debt Obligations (Narrative) (Details) (USD $)	9 Months Ended							9 Months Ended			9 Months Ended		9 Months Ended			9 Months Ended	4 Months Ended		9 Months Ended					9 Months Ended		9 Months Ended		9 Months Ended		9 Months Ended		9 Months Ended			9 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Sep. 30, 2014 DP&L [Member]	Mar. 31, 2014 DP&L [Member]	Dec. 31, 2013 DP&L [Member]	Oct. 20, 2014 DPL [Member] Cash on hand [Member] Subsequent Event [Member]	Sep. 30, 2014 DPL [Member] Credit Facility [Member]	Oct. 06, 2014 Senior Unsecured notes maturing October 2019 at 6.75% [Member] DPL [Member] Subsequent Event [Member]	Sep. 30, 2014 Senior Unsecured notes maturing October 2019 at 6.75% [Member] DPL [Member] Subsequent Event [Member]	Sep. 30, 2014 U.S. Government note maturing in February 2061 - 4.20% [Member]	Dec. 31, 2013 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]	Dec. 31, 2013 U.S. Government note maturing in February 2061 - 4.20% [Member] DP&L [Member]	Mar. 31, 2014 Related Party Notes Payable [Member]	Sep. 30, 2014 Revolving Credit Agreeement with Bank Group Expiring 2018 [Member]	May 10, 2013 Revolving Credit Agreeement with Bank Group Expiring 2018 [Member] DP&L [Member]	Sep. 30, 2014 Revolving Credit Agreeement with Bank Group Expiring 2018 [Member] DP&L [Member]	Sep. 30, 2014 Revolving Credit Agreeement with Bank Group Expiring 2018 [Member] DPL [Member]	Sep. 30, 2014 Senior Unsecured Notes at 6.50% maturing on October 15, 2016 [Member]	Dec. 31, 2013 Senior Unsecured Notes at 6.50% maturing on October 15, 2016 [Member]	Sep. 06, 2014 Senior Unsecured Notes at 6.50% maturing on October 15, 2016 [Member] DPL [Member] Scenario, Forecast [Member]	Oct. 06, 2014 Senior Unsecured Notes at 6.50% maturing on October 15, 2016 [Member] DPL [Member] Tender offer [Member] Subsequent Event [Member]	Sep. 30, 2014 Ten Year Senior Unsecured Notes at 7.25% maturing at October 15, 2021 [Member]	Dec. 31, 2013 Ten Year Senior Unsecured Notes at 7.25% maturing at October 15, 2021 [Member]	Sep. 30, 2014 First Mortgage Bonds Maturing in September 2016	Dec. 31, 2013 First Mortgage Bonds Maturing in September 2016	Sep. 30, 2014 First Mortgage Bonds Maturing in September 2016 DP&L [Member]	Dec. 31, 2013 First Mortgage Bonds Maturing in September 2016 DP&L [Member]	Sep. 30, 2014 Note to DPL Capital Trust II Maturing in September 2031 - 8.125% [Member]	Dec. 31, 2013 Note to DPL Capital Trust II Maturing in September 2031 - 8.125% [Member]	Sep. 30, 2014 Note to DPL Capital Trust II Maturing in September 2031 - 8.125% [Member] Subsequent Event [Member]	Sep. 30, 2014 Pollution control series maturing in November 2040 - variable rates: 0.04% - 0.26% and 0.06% - 0.32% [Member]	Dec. 31, 2013 Pollution control series maturing in November 2040 - variable rates: 0.04% - 0.26% and 0.06% - 0.32% [Member]	Sep. 30, 2014 Pollution control series maturing in November 2040 - variable rates: 0.04% - 0.26% and 0.06% - 0.32% [Member] DP&L [Member]	Dec. 31, 2013 Pollution control series maturing in November 2040 - variable rates: 0.04% - 0.26% and 0.06% - 0.32% [Member] DP&L [Member]	Sep. 30, 2014 Bank Term Loan maturing in May 2018 [Member]	Dec. 31, 2013 Bank Term Loan maturing in May 2018 [Member]
Debt Instrument, Face Amount							$ 100,000,000		$ 200,000,000													$ 280,000,000	$ 300,000,000
Repurchase of Securities at Fair Value																																5,000,000
Additional principal amount of senior notes to be raised	1,250,000,000																			450,000,000				800,000,000
Debt Instrument, Maturity Date Range, End											Feb. 01, 2061		Feb. 01, 2061							Oct. 01, 2016				Oct. 01, 2021		Sep. 01, 2016		Sep. 01, 2016		Sep. 01, 2031			Nov. 01, 2040		Nov. 01, 2040		May 01, 2018
Notes Payable, Related Parties					15,000,000
Unsecured revolving credit agreement																	300,000,000	300,000,000	100,000,000
Withdrawals from revolving credit facilities	115,000,000	50,000,000
Increase/decrease additional facility																100,000,000	100,000,000		100,000,000
Letter of credit sublimit																100,000,000	100,000,000		100,000,000
Letters of credit outstanding								2,300,000										700,000
Line of Credit Facility, Remaining Borrowing Capacity								97,700,000										299,300,000
Long-term Debt, Gross											(18,100,000)	(18,300,000)	18,100,000	18,200,000						330,000,000	430,000,000			780,000,000	780,000,000	445,000,000	445,000,000	445,000,000	445,000,000	19,700,000	19,600,000		100,000,000	100,000,000	100,000,000	100,000,000	150,000,000	180,000,000
Premium Expenses																				1,900,000				500,000
Current portion - long-term debt	110,100,000		10,200,000	100,000		200,000														100,000,000
Repayments of debt								$ 50,000,000												$ 20,000,000				$ 20,000,000
Debt instrument interest percentage										6.75%	4.20%		4.20%		2.00%					6.50%				7.25%		1.875%		1.875%		8.125%