Debt Obligations (Narrative) (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended				0 Months Ended					12 Months Ended			12 Months Ended			12 Months Ended				1 Months Ended			1 Months Ended	0 Months Ended				0 Months Ended	12 Months Ended		0 Months Ended	12 Months Ended						12 Months Ended		12 Months Ended			12 Months Ended		12 Months Ended		12 Months Ended			12 Months Ended				12 Months Ended	0 Months Ended	12 Months Ended
	Oct. 03, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 04, 2008	May 10, 2013 Cash on hand [Member]	May 10, 2013 Credit Facility [Member]	May 10, 2013 Other Debt [Member]	Dec. 31, 2013 DP&L [Member]	Dec. 31, 2012 DP&L [Member]	Dec. 31, 2013 U.S. Government note maturing in February 2061 - 4.20% [Member]	Dec. 31, 2012 U.S. Government note maturing in February 2061 - 4.20% [Member]	Mar. 01, 2011 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] DP&L [Member]	Dec. 31, 2012 U.S. Government note maturing in February 2061 - 4.20% [Member] DP&L [Member]	Mar. 01, 2011 U.S. Government note maturing in February 2061 - 4.20% [Member] DP&L [Member]	Dec. 31, 2012 Revolving Credit Agreement with Bank Group [Member]	Oct. 31, 2012 Revolving Credit Agreement with Bank Group [Member]	Aug. 31, 2011 Revolving Credit Agreement with Bank Group [Member]	Aug. 24, 2011 Revolving Credit Agreement with Bank Group [Member]	Apr. 20, 2010 Revolving Credit Agreement with Bank Group [Member] DP&L [Member]	Aug. 24, 2011 Revolving Credit Agreement with Bank Group [Member] DPL [Member]	Oct. 19, 2012 Revolving Credit Agreement with Bank Group [Member] DPL [Member]	Aug. 24, 2011 Revolving Credit Agreement with Bank Group expiring 2015 [Member] DP&L [Member]	May 10, 2013 Revolving Credit Agreement with Bank Group expiring 2015 [Member] DPL [Member]	May 10, 2013 Revolving Credit Agreeement with Bank Group Expiring 2018 [Member] DP&L [Member]	Dec. 31, 2013 Revolving Credit Agreeement with Bank Group Expiring 2018 [Member] DP&L [Member]	May 10, 2013 Revolving Credit Agreeement with Bank Group Expiring 2018 [Member] DPL [Member]	Oct. 03, 2011 Five Year Senior Unsecured Notes at 6.50% maturing on October 15, 2016 [Member]	Dec. 31, 2013 Five Year Senior Unsecured Notes at 6.50% maturing on October 15, 2016 [Member]	Dec. 31, 2012 Five Year Senior Unsecured Notes at 6.50% maturing on October 15, 2016 [Member]	Oct. 03, 2011 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]	Oct. 03, 2013 Ten Year Senior Unsecured Notes at 7.25% maturing at October 15, 2021 [Member]	Dec. 31, 2012 Ten Year Senior Unsecured Notes at 7.25% maturing at October 15, 2021 [Member]	Dec. 31, 2013 First Mortgage Bonds Maturing October 2013 [Member]	Dec. 31, 2013 First Mortgage Bonds Maturing October 2013 [Member] DP&L [Member]	Aug. 24, 2011 Unsecured Term Loan Agreement [Member]	Dec. 31, 2013 First Mortgage Bonds Maturing in September 2016 - 1.9%	Sep. 19, 2013 First Mortgage Bonds Maturing in September 2016 - 1.9%	Dec. 31, 2013 First Mortgage Bonds Maturing in September 2016 - 1.9% DP&L [Member]	Sep. 19, 2013 First Mortgage Bonds Maturing in September 2016 - 1.9% DP&L [Member]	May 10, 2013 First Mortgage Bonds Maturing in September 2016 - 1.9% DPL [Member]	Dec. 31, 2013 Note to DPL Capital Trust II Maturing in September 2031 - 8.125% [Member]	Dec. 31, 2012 Note to DPL Capital Trust II Maturing in September 2031 - 8.125% [Member]	Dec. 31, 2013 Pollution control series maturing in November 2040 - variable rates: 0.04% - 0.26% and 0.06% - 0.32% [Member]	Dec. 31, 2012 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] DP&L [Member]	Dec. 31, 2012 Pollution control series maturing in November 2040 - variable rates: 0.04% - 0.26% and 0.06% - 0.32% [Member] DP&L [Member]	Dec. 04, 2008 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 Bank Term Loan - variable rates: 2.22% - 2.30% and 1.48% - 4.25% [Member]	Dec. 31, 2012 Bank Term Loan - variable rates: 2.22% - 2.30% and 1.48% - 4.25% [Member]	Dec. 31, 2013 Bank Term Loan - variable rates: 2.22% - 2.30% and 1.48% - 4.25% [Member] DPL [Member]	Aug. 24, 2011 Bank Term Loan - variable rates: 2.22% - 2.30% and 1.48% - 4.25% [Member] DPL [Member]	Dec. 31, 2013 Bank Term Loan maturing in May 2018 [Member]	May 10, 2013 Bank Term Loan maturing in May 2018 [Member] DPL [Member]	Dec. 31, 2013 Bank Term Loan maturing in May 2018 [Member] DPL [Member]
Additional principal amount of senior notes to be raised	$ 1,250.0																											$ 450.0			$ 800.0
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			Aug. 01, 2014				May 01, 2018
Unsecured revolving credit agreement																	75.0	125.0	125.0	200.0	125.0	75.0	200.0		300.0		100.0										425.0																		100.0
Withdrawals from revolving credit facilities																								50.0
Increase/decrease additional facility																				50.0			50.0		100.0																														50.0
Letter of credit sublimit																75.0				50.0	75.0		50.0		100.0																														100.0
Letters of credit outstanding																										0.4
Collateralized debt				100.0																																													100.0
Line of Credit Facility, Remaining Borrowing Capacity																										299.6
Long-term Debt, Gross		2,284.2	2,025.0					876.9	332.7	18.3	18.3	18.7	18.2	18.3	18.7														430.0	450.0		780.0		800.0	470.0	470.0		444.3	445.0	445.0	445.0		19.6	19.6	100.0		100.0				425.0	425.0	425.0	180.0	200.0	190.0
Premium Expenses																													1.9			0.5
Current portion - long-term debt		10.2	584.9					0.2	570.4																																					100.0		100.0						10.0
Term Loan Amortization Year 1																																										5.00%
Repayments of debt					$ 175.0	$ 50.0	$ 200.0																						$ 20.0			$ 20.0																								$ 10.0
Debt instrument interest percentage										4.20%		4.20%	4.20%		4.20%													6.50%	6.50%		7.25%	7.25%	7.25%					1.875%		1.875%			8.125%											2.42%