Summary of Significant Accounting Policies (Narrative) (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	11 Months Ended	12 Months Ended
	Dec. 31, 2011	Nov. 27, 2011	Dec. 31, 2013 sqmi employee	Dec. 31, 2012	Dec. 31, 2011
Service Area Square Miles			6,000
Service Area By County			24
Approximate number of retail customers			515,000
DPLER Customers That Are DPL Electric Distribution Customers			130,000
Approximate number of DPLER customers			308,000
Entity number of employees			1,266
Number of coal fired power plants			7
Employees under a collective bargaining agreement which expires in October-2011			59.00%
Capitalized interest for unregulated generation propety	$ 0.5	$ 3.9	$ 1.5	$ 4.0
Straight-line depreciation average annual composite basis			5.80%	4.80%	5.80%
Asset Removal Costs	112.4		114.9	112.1	112.4
Additional Insurance Claims Cost			18.8	17.7
Investment in trust			0.4	0.5
Notes payable to trust			19.6
DP&L [Member]
Service Area Square Miles			6,000
Approximate number of retail customers			515,000
Entity number of employees			1,218
Number of coal fired power plants			7
Employees under a collective bargaining agreement which expires in October-2011			62.00%
Capitalized interest for unregulated generation propety			1.5	4.0	4.4
Reduction of future depreciation due to asset impairment				7.1
Reduction of current depreciation due to asset impairment			5.4	1.8
Straight-line depreciation average annual composite basis			4.40%	4.20%	2.60%
Asset Removal Costs	112.4		114.9	112.1	112.4
Additional Insurance Claims Cost			$ 18.8	$ 17.7