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- Definition

Debt Covenant, Leverage Ratio, Maximum

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- Definition

Debt Covenant, Total Debt to Total Capitalization Ratio, Maximum

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- Definition

Debt Instrument, Debt Covenant, EBITDA to Interest Expense, EBITDA Minimum

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Debt Instrument, Debt Covenant, EBITDA to Interest Calculation, Number of Quarters

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Debt Instrument, Debt Covenant, Total Debt to EBITDA Ratio

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Debt Instrument, Number of Financial Covenants

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- Definition

Letter Of Credit Sublimit

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Line of Credit Facility, Additional Borrowing Capacity

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- Definition

Make Whole Premium

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Number of Interest Rate Swaps

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Total Long-term Debt At Subsidiary With Purchase Accounting 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 (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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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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 (premium).

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Gross amount of debt extinguished.

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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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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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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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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 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 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 (Narrative) (Details) $ in Millions					12 Months Ended
Debt (Narrative) (Details) $ in Millions	Dec. 31, 2022 USD ($)	Sep. 30, 2022 USD ($)	Jun. 01, 2020 USD ($)	Jun. 06, 2019 USD ($)	Dec. 31, 2020 USD ($) debt_covenant fiscal_quarter	Dec. 31, 2019 USD ($) Number_of_interest_rate_swaps	Dec. 31, 2018 USD ($)	Aug. 03, 2020 USD ($)	May 07, 2019 USD ($)
Debt Instrument [Line Items]
Current portion - long-term debt					$ 0.2
Unamortized adjustments to market value from purchase accounting					3.5
Letter Of Credit Sublimit						$ 75.0
Line of Credit Facility, Additional Borrowing Capacity						50.0
Issuance of long-term debt					555.0	821.7	$ 0.0
Unamortized Deferred Financing Costs					(10.2)	(5.9)
Current portion - long-term debt					$ 0.2	139.8
Debt Covenant, Leverage Ratio, Maximum					0.67
Debt Covenant, Interest Coverage Ratio, Minimum			2.25		1.70
Debt Instrument, Unamortized Discount (Premium), Net					$ 0.9	1.0
Total Long-term Debt At Subsidiary With Purchase Accounting Adjustments					574.1	574.4
Long-term Debt, Excluding Current Maturities					1,393.4	1,223.3
Long-Term Debt, Maturity, Year Two					0.2
Long-term Line of Credit					80.0	104.0
Line of Credit Facility, Current Borrowing Capacity			$ 125.0
Line of Credit Facility, Maximum Borrowing Capacity					110.0	125.0
Debt Instrument, Debt Covenant, EBITDA to Interest Expense, EBITDA Minimum					$ 125.0
Debt Instrument, Debt Covenant, Total Debt to EBITDA Ratio					7.00
Phase 2 [Member]
Debt Instrument [Line Items]
Debt Instrument, Debt Covenant, EBITDA to Interest Expense, EBITDA Minimum	$ 150.0
Phase 1
Debt Instrument [Line Items]
Debt Instrument, Debt Covenant, EBITDA to Interest Expense, EBITDA Minimum		$ 130.0
Forecast [Member]
Debt Instrument [Line Items]
Debt Covenant, Interest Coverage Ratio, Minimum	2.00	1.75
Debt Instrument, Debt Covenant, EBITDA to Interest Expense, EBITDA Minimum	$ 150.0	$ 130.0
THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Current portion - long-term debt					$ 0.2
Letter Of Credit Sublimit					75.0
Line of Credit Facility, Additional Borrowing Capacity					100.0
Issuance of long-term debt					140.0	422.3	$ 0.0
Unamortized Deferred Financing Costs						(5.4)
Current portion - long-term debt					0.2	139.8
Unamortized Deferred Financing Costs (Subsidiary)					(5.7)	(5.4)
Debt Instrument, Unamortized Discount (Premium), Net					2.6	2.7
Long-term Debt, Excluding Current Maturities					573.9	434.6
Long-Term Debt, Maturity, Year Two					0.2
Long-term Line of Credit					20.0	$ 40.0
Line of Credit Facility, Maximum Borrowing Capacity					175.0
Number of Interest Rate Swaps \| Number_of_interest_rate_swaps						2
3.95% Senior Notes due 2049 [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Issuance of long-term debt				$ 425.0	425.0
Long-term Debt, Gross					425.0
Extinguishment of Debt, Amount				$ 435.0	$ 435.0
Debt instrument interest percentage					3.95%
Senior Unsecured Notes At 6.80 Maturing On October 2019 [Member]
Debt Instrument [Line Items]
Make Whole Premium						$ 1.5
Extinguishment of Debt, Amount						$ 99.0
Debt instrument interest percentage						6.75%
U.S. Government note maturing in 2061 - 4.20% [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 17.4	$ 17.5
U.S. Government note maturing in 2061 - 4.20% [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 17.4	17.5
Debt instrument interest percentage					4.20%
Five Year Senior Unsecured Notes At6.75 Maturing October152019 [Member]
Debt Instrument [Line Items]
Debt instrument interest percentage					7.25%
DPL Revolving Credit Agreement and Term Loan Maturing July 2020 [Member]
Debt Instrument [Line Items]
Number of financial covenants \| debt_covenant					2
Number of prior quarters included in debt to EBITDA ratio \| fiscal_quarter					4
Debt Covenant, Interest Coverage Ratio, Minimum					2.50
Senior Unsecured Bonds at 7.25% maturing in 2021 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross						380.0			$ 780.0
Make Whole Premium						41.4
Extinguishment of Debt, Amount						$ 400.0
Debt instrument interest percentage					7.25%	7.25%
Note to DPL Capital Trust II Maturing in 2031 - 8.125% [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 15.6	$ 15.6
Debt instrument interest percentage					8.125%
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
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
3.20% First Mortgage Bonds due 2040 [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Issuance of long-term debt					$ 140.0
Debt Instrument, Interest Rate, Effective Percentage Rate Range, Minimum (Deprecated 2016-01-31)					3.20%
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
4.125% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Issuance of long-term debt					$ 415.0
Debt instrument interest percentage					4.125%
3.2% Senior Notes due 2049
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 140.0
Debt instrument interest percentage					3.20%
3.2% Senior Notes due 2049 \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 140.0
Debt instrument interest percentage					3.20%
Ten Year Senior Unsecured Notes At725 Maturing At October152025
Debt Instrument [Line Items]
Debt instrument interest percentage					4.125%
Five Year Senior Unsecured Notes At 4125 Maturing on July12025
Debt Instrument [Line Items]
Long-term Debt, Gross					$ 415.0	0.0
Make Whole Premium					30.8
Extinguishment of Debt, Amount					380.0
Debt [Member]
Debt Instrument [Line Items]
Long-term Debt and Lease Obligation, Including Current Maturities					1,393.6	1,363.1
Debt [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt and Lease Obligation, Including Current Maturities					$ 574.1	$ 574.4
Minimum [Member] \| One Point One Six To Two Point Four Seven Bonds Maturing In August Two Thousand Twenty
Debt Instrument [Line Items]
Debt instrument interest percentage					1.16%
Minimum [Member] \| One Point One Six To Two Point Four Seven Bonds Maturing In August Two Thousand Twenty \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Debt instrument interest percentage					1.16%
Minimum [Member] \| Two Point Four To Three Point Zero Seven Bonds Maturing In August Two Thousand Twenty
Debt Instrument [Line Items]
Debt instrument interest percentage						2.40%
Minimum [Member] \| Two Point Four To Three Point Zero Seven Bonds Maturing In August Two Thousand Twenty \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Debt instrument interest percentage						2.40%
Maximum [Member] \| One Point One Six To Two Point Four Seven Bonds Maturing In August Two Thousand Twenty
Debt Instrument [Line Items]
Debt instrument interest percentage					2.47%
Maximum [Member] \| One Point One Six To Two Point Four Seven Bonds Maturing In August Two Thousand Twenty \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Debt instrument interest percentage					2.47%
Maximum [Member] \| Two Point Four To Three Point Zero Seven Bonds Maturing In August Two Thousand Twenty
Debt Instrument [Line Items]
Debt instrument interest percentage						3.07%
Maximum [Member] \| Two Point Four To Three Point Zero Seven Bonds Maturing In August Two Thousand Twenty \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Debt instrument interest percentage						3.07%