Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities:
Net income	$ 26.0	$ 20.4
Adjustments to reconcile net income / (loss) to net cash from operating activities:
Depreciation and amortization	13.9	41.6
Gain (Loss) on Extinguishment of Debt	(44.9)	(6.4)
Deferred income taxes	8.6	(20.0)
Impairment of Long-Lived Assets Held-for-use	0.0	1.2
Gain (Loss) on Disposition of Business, Including Discontinued Operation	(0.1)	13.5
Gain (Loss) on Sale of Assets and Asset Impairment Charges	0.9	1.1
Changes in certain assets and liabilities:
Accounts receivable, net	24.7	20.9
Inventories	(4.0)	13.5
Taxes applicable to subsequent years	37.5	39.3
Deferred regulatory costs, net	(6.7)	(6.7)
Accounts payable	7.8	(11.1)
Accrued taxes	(41.7)	(19.9)
Accrued interest	(2.4)	(1.7)
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits	(8.7)	(5.3)
Other	(1.7)	4.5
Net Cash Provided by (Used in) Operating Activities	99.0	97.7
Cash flows from investing activities:
Capital expenditures	(63.4)	(50.7)
Proceeds from disposal and sale of business	0.0	234.9
Payments for Removal Costs	0.0	(14.5)
Proceeds from Sale of Property, Plant, and Equipment	0.0	10.6
Proceeds from Insurance Settlement, Investing Activities	0.0	2.8
Other investing activities, net	(3.2)	(0.5)
Net cash provided by / (used in) investing activities	(66.6)	182.6
Cash flows from financing activities:
Payments of Deferred Finance Costs	(8.1)	0.0
Repayments of Lines of Credit	(10.0)	(30.0)
Proceeds from Issuance of Long-term Debt	821.7	0.0
Proceeds from Lines of Credit	73.0	30.0
Repayment of long-term debt	(978.0)	(238.3)
Proceeds from (Payments for) Other Financing Activities	(0.1)	0.0
Net cash used in financing activities	(101.5)	(238.3)
Cash, cash equivalents, and restricted cash:
Net Cash Provided by (Used in) Discontinued Operations	0.0	1.5
Restricted Cash and Cash Equivalents	42.6	68.4
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect	(69.1)	43.5
Supplemental cash flow information:
Interest paid, net of amounts capitalized	45.3	49.2
Proceeds from Income Tax Refunds	0.9	(2.0)
Non-cash financing and investing activities:
Accruals for capital expenditures	20.5	7.2
Non-cash Proceeds from Sale of Business	0.0	4.1
Non-cash capital contribution	0.0	26.7
THE DAYTON POWER AND LIGHT COMPANY [Member]
Cash flows from operating activities:
Net income	58.8	30.7
Adjustments to reconcile net income / (loss) to net cash from operating activities:
Depreciation and amortization	35.5	37.4
Gain (Loss) on Extinguishment of Debt	0.0	(0.6)
Deferred income taxes	(3.5)	(6.7)
Gain (Loss) on Disposition of Business	0.0	(12.4)
Changes in certain assets and liabilities:
Accounts receivable, net	18.9	10.9
Inventories	(3.5)	(0.3)
Taxes applicable to subsequent years	36.2	36.4
Deferred regulatory costs, net	(6.7)	(6.7)
Accounts payable	6.0	(5.6)
Accrued taxes	(33.0)	(31.7)
Accrued interest	1.5	0.0
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits	(8.6)	(4.4)
Other	2.4	6.1
Net Cash Provided by (Used in) Operating Activities	104.0	79.1
Cash flows from investing activities:
Capital expenditures	(62.2)	(44.5)
Payments for Removal Costs	0.0	(14.5)
Proceeds from Sale of Property, Plant, and Equipment	0.0	10.6
Other investing activities, net	(3.2)	(0.1)
Net cash provided by / (used in) investing activities	(65.4)	(48.5)
Cash flows from financing activities:
Payments of Deferred Finance Costs	(3.8)	0.0
Repayments of Lines of Credit	0.0	(30.0)
Proceeds from Issuance of Long-term Debt	422.3	0.0
Proceeds from Lines of Credit	0.0	30.0
Repayment of long-term debt	(436.1)	(62.2)
Payments of Ordinary Dividends, Common Stock	(70.0)	(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	(87.7)	(6.0)
Cash, cash equivalents, and restricted cash:
Restricted Cash and Cash Equivalents	17.1	30.2
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect	(49.1)	24.6
Supplemental cash flow information:
Interest paid, net of amounts capitalized	10.3	11.5
Income Taxes Paid, Net	12.0	2.7
Non-cash financing and investing activities:
Accruals for capital expenditures	20.4	5.6
Other Operating Income (Expense) [Member]
Adjustments to reconcile net income / (loss) to net cash from operating activities:
Impairment of Long-Lived Assets Held-for-use	0.0	1.2
Gain (Loss) on Disposition of Business	$ 0.0	$ (11.7)