Consolidated Statements of Comprehensive Income/(Loss) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net income (loss)	$ 28.7us-gaap_ProfitLoss	$ (249.0)us-gaap_ProfitLoss
Available-for-sale securities activity:
Change in fair value of available-for-sale securities	0.5	(0.3)
Reclassification to earnings of available-for-sale securities, net of income tax expense/(benefit)	(0.4)	0.2
Total change in fair value of available-for-sale securities	0.1	(0.1)
Derivative activity:
Change in derivative fair value	0.1	(12.9)
Reclassification of earnings, net of income tax (expense)/benefit	0.6	5.5
Total change in fair value of derivatives	0.7	(7.4)
Pension and postretirement activity:
Reclassification to earnings of Pension	0.1
Total change in unfunded pension obligation	0.1
Other comprehensive income / (loss)	0.9	(7.5)
Net comprehensive income / (loss)	29.6	(256.5)
THE DAYTON POWER AND LIGHT COMPANY [Member]
Net income (loss)	36.5	9.4
Available-for-sale securities activity:
Change in fair value of available-for-sale securities	0.5	(0.3)
Reclassification to earnings of available-for-sale securities, net of income tax expense/(benefit)	(0.4)	0.2
Total change in fair value of available-for-sale securities	0.1	(0.1)
Derivative activity:
Change in derivative fair value	0.1	(12.9)
Reclassification of earnings, net of income tax (expense)/benefit	0.5	5.7
Total change in fair value of derivatives	0.6	(7.2)
Pension and postretirement activity:
Reclassification to earnings of Pension	0.9	0.6
Total change in unfunded pension obligation	0.9	0.6
Other comprehensive income / (loss)	1.6	(6.7)
Net comprehensive income / (loss)	$ 38.1	$ 2.7

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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