Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities:
Net income	$ 42.1	$ 16.9
Adjustments to reconcile net income / (loss) to net cash from operating activities:
Depreciation and amortization	(3.1)	20.1
Charge for early retirement of debt	0.0	0.7
Deferred income taxes	5.2	(41.7)
Gain (Loss) on Disposition of Business	0.0	(11.7)
Gain (Loss) on Disposition of Business, Including Discontinued Operation	(0.1)	13.6
Gain (Loss) on Sale of Assets and Asset Impairment Charges	0.9	0.6
Changes in certain assets and liabilities:
Accounts receivable, net	4.1	5.9
Inventories	(1.2)	3.2
Taxes applicable to subsequent years	18.7	19.7
Deferred regulatory costs, net	7.7	(2.1)
Accounts payable	(14.0)	(0.9)
Accrued taxes	(35.2)	8.2
Accrued interest	15.6	17.6
Increase (Decrease) in Security Deposits	7.7	0.6
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits	(6.9)	(5.9)
Other	(4.9)	(5.9)
Net Cash Provided by (Used in) Operating Activities	36.6	50.6
Cash flows from investing activities:
Capital expenditures	(34.3)	(27.3)
Proceeds from disposal and sale of business	0.0	234.9
Payments for Removal Costs	0.0	(14.5)
Other investing activities, net	0.0	2.3
Net cash provided by / (used in) investing activities	(34.3)	195.4
Cash flows from financing activities:
Repayments of Lines of Credit	0.0	(15.0)
Proceeds from Lines of Credit	0.0	25.0
Repayment of long-term debt	(1.1)	(131.1)
Proceeds from (Payments for) Other Financing Activities	(0.1)	0.0
Net cash used in financing activities	(1.2)	(121.1)
Net Cash Provided by (Used in) Discontinued Operations	0.0	(1.3)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect	1.1	123.6
Other deferred credits	7.9
Supplemental cash flow information:
Interest paid, net of amounts capitalized	6.7	7.0
Proceeds from Income Tax Refunds	0.0	0.0
Non-cash financing and investing activities:
Accruals for capital expenditures	4.4	8.9
Restricted Cash and Cash Equivalents	112.8	148.5
Non-cash Proceeds from Sale of Business	0.0	4.1
Non-cash capital contribution	1.5	44.6
THE DAYTON POWER AND LIGHT COMPANY [Member]
Cash flows from operating activities:
Net income	29.0	15.7
Adjustments to reconcile net income / (loss) to net cash from operating activities:
Depreciation and amortization	18.0	18.6
Charge for early retirement of debt	0.0	0.5
Deferred income taxes	(0.9)	3.6
Gain (Loss) on Disposition of Business	0.0	(12.4)
Changes in certain assets and liabilities:
Accounts receivable, net	2.6	(2.3)
Inventories	(0.5)	(0.2)
Taxes applicable to subsequent years	18.1	17.8
Deferred regulatory costs, net	7.7	(2.1)
Accounts payable	(12.7)	7.7
Accrued taxes	(27.4)	(36.3)
Accrued interest	0.1	0.3
Increase (Decrease) in Security Deposits	7.7	0.6
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits	(6.8)	(5.5)
Other	(5.4)	(0.2)
Net Cash Provided by (Used in) Operating Activities	29.5	30.6
Cash flows from investing activities:
Capital expenditures	(33.7)	(24.6)
Payments for Removal Costs	0.0	(14.5)
Other investing activities, net	0.0	(0.3)
Net cash provided by / (used in) investing activities	(33.7)	(39.4)
Cash flows from financing activities:
Repayments of Lines of Credit	0.0	(15.0)
Proceeds from Lines of Credit	0.0	25.0
Repayment of long-term debt	(1.1)	(61.1)
Payments of Ordinary Dividends, Common Stock	0.0	(23.8)
Proceeds from Contributions from Parent	0.0	80.0
Proceeds from (Payments for) Other Financing Activities	(0.1)	0.0
Net cash used in financing activities	(1.2)	5.1
Net Cash Provided by (Used in) Discontinued Operations	0.0	0.0
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect	(5.4)	(3.7)
Other deferred credits	7.5
Supplemental cash flow information:
Interest paid, net of amounts capitalized	5.9	5.5
Income Taxes Paid, Net	0.0	0.0
Non-cash financing and investing activities:
Accruals for capital expenditures	4.8	4.6
Restricted Cash and Cash Equivalents	$ 60.8	$ 1.9