Debt Covenant, Total Debt to Total Capitalization Ratio, Maximum

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Long Term Debt Maturities Repayments Of Principal, Total

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Total Maturities Before Unamortized Adjustments

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Unamortized adjustments to market value from purchase accounting

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Unamortized Deferred Financing Costs

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Unamortized Deferred Financing Costs, Consolidated

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Unamortized Deferred Financing Costs (Subsidiary)

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of long-term debt and lease obligation, including portion classified as current.

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No definition available.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Debt (Long-term Debt Maturities) (Details) $ in Millions	12 Months Ended
Debt (Long-term Debt Maturities) (Details) $ in Millions	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Aug. 03, 2020 USD ($)
Debt Instrument [Line Items]
Long-term Line of Credit	$ 65.0	$ 80.0
Line of Credit Facility, Maximum Borrowing Capacity	110.0
Proceeds from Issuance of Long-term Debt	0.0	555.0	$ 821.7
Unamortized Deferred Financing Costs, Consolidated	(14.0)
Current portion - long-term debt	0.2
Long-Term Debt, Maturity, Year Two	0.2
2018	0.2
2019	415.2
2020	0.2
Thereafter	996.8
Total Maturities	1,412.8
Unamortized adjustments to market value from purchase accounting	(3.3)
Total long-term debt	1,395.5
Unamortized Deferred Financing Costs	(8.6)	(10.2)
Current portion - long-term debt	0.2	0.2
Long-term Debt, Excluding Current Maturities	1,395.3	1,393.4
THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	0.0	20.0
Proceeds from Issuance of Long-term Debt	0.0	140.0	$ 422.3
Unamortized Deferred Financing Costs, Consolidated	(5.4)
Current portion - long-term debt	0.2
Long-Term Debt, Maturity, Year Two	0.2
2018	0.2
2019	0.2
2020	0.2
Thereafter	581.2
Total Maturities	582.2
Debt Instrument, Unamortized Discount	(2.5)	(2.6)
Total long-term debt	574.3
Unamortized Deferred Financing Costs		(5.7)
Current portion - long-term debt	0.2	0.2
Long-term Debt, Excluding Current Maturities	574.1	573.9
Unamortized Deferred Financing Costs (Subsidiary)	$ (5.4)	(5.7)
3.95% Senior Notes due 2049 [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.95%
Long-term Debt, Gross	$ 425.0	425.0
Ten Year Senior Unsecured Bonds At 435 Maturing At April 15 2029 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.35%
Senior Unsecured Bonds at 7.25% maturing in 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.25%
One Point One Three To One Point One Seven Bonds Maturing In August Two Thousand Twenty [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		140.0
One Point One Three To One Point One Seven Bonds Maturing In August Two Thousand Twenty [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		140.0
Four Point Two Zero Percentage Of U S Government Note Maturing In February Two Thousand Sixty One [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 17.2	17.4
Four Point Two Zero Percentage Of U S Government Note Maturing In February Two Thousand Sixty One [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.20%
Long-term Debt, Gross	$ 17.2	17.4
Variable Rate Notes Backed by Term Loan and First Mortgage Bonds [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 140.0	140.0		$ 140.0
Revolving Credit Facility [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Debt Covenant, Total Debt to Total Capitalization Ratio, Maximum	0.67
Debt [Member]
Debt Instrument [Line Items]
Long-term Debt and Lease Obligation, Including Current Maturities	$ 1,395.5	1,393.6
Debt [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt and Lease Obligation, Including Current Maturities	$ 574.3	$ 574.1