Overview and Summary of Significant Accounting Policies (Accounting for Taxes Collected from Customers and Remitted to Governmental Authorities) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Excise Taxes Collected	$ 46.6	$ 49.2	$ 48.7
THE DAYTON POWER AND LIGHT COMPANY [Member]
Excise Taxes Collected	$ 46.6	$ 49.2	$ 48.7

The excise taxes collected by a public utility and reported in revenues if the amount of excise taxes is equal to 1 percent or more of such total.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(1)(e))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

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Balance Type:	credit
Period Type:	duration