Dispositions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	$ 22.4	$ (11.9)	$ 31.5
Payments for Removal Costs	3.9	8.9	51.0
THE DAYTON POWER AND LIGHT COMPANY [Member]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	52.8	58.1	124.3
Payments for Removal Costs	0.0	7.0	$ 0.0
THE DAYTON POWER AND LIGHT COMPANY [Member] | Hutchings
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest		4.7
Payments for Removal Costs		$ 7.0
Payments for Removal Costs, Additional Payments	$ 2.3