Long Term Debt Maturities Repayments Of Principal, Total

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Total Long-term Debt At Subsidiary With Purchase Accounting Adjustments

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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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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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Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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Amount, after accumulated amortization, of debt discount (premium).

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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 long-term debt and capital lease obligations including current maturities.

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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 requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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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Debt (Long-term Debt) (Details) - USD ($) $ in Millions	12 Months Ended
Debt (Long-term Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2019	May 07, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	$ 140.2
Unamortized Deferred Financing Costs	(5.9)		$ (4.3)
Debt Instrument, Unamortized Discount (Premium), Net	(1.0)		(0.5)
Total long-term debt at subsidiary	574.4		586.1
Less: current portion	(139.8)		(103.6)
Long-term debt, net of current portion	1,223.3		1,372.3
Long-term Debt, Maturities, Repayments of Principal in Year Two	380.2
Long-term Debt, Maturities, Repayments of Principal in Year Three	0.2
Long-term Debt, Maturities, Repayments of Principal in Year Four	0.2
Long-term Debt, Maturities, Repayments of Principal in Year Five	0.2
Long-term Debt, Maturities, Repayments of Principal after Year Five	857.1
Total Maturities Before Unamortized Adjustments	1,378.1
Unamortized adjustments to market value from purchase accounting	3.7
Unamortized Deferred Financing Costs, Consolidated	(11.3)
Long Term Debt Maturities Repayments Of Principal, Total	1,363.1
Long-term Line of Credit	104.0		0.0
THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Unamortized Deferred Financing Costs (Subsidiary)	(5.4)		(6.3)
Debt Instrument, Unamortized Discount (Premium), Net	(2.7)		(1.4)
Long-term Line of Credit	40.0		0.0
3.95% Senior Notes due 2049 [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 425.0
Debt instrument maturity year	Jan. 01, 2049
Debt instrument interest percentage	3.95%
Ten Year Senior Unsecured Bonds At 435 Maturing At April 15 2029 [Member]
Debt Instrument [Line Items]
Debt instrument maturity year	Apr. 15, 2029
Debt instrument interest percentage	4.35%
Term Loan Maturing 2022 (DPL) [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 0.0		436.1
Debt instrument maturity year	Aug. 24, 2022
Tax-exempt First Mortgage Bonds - rates from: 2.49% - 2.93% (a) and 1.29% - 1.42% (b)
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 140.0
Debt instrument maturity year	Aug. 01, 2020
Two Point Four Nine to Two Point Nine Three and One Point Two Nine to One Point Four Two Bonds Maturing In Two Thousand Twenty [Member] [Domain]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 140.0		140.0
U.S. Government note maturing in 2061 - 4.20% [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 17.5		17.7
Debt instrument maturity year	Feb. 01, 2061
Debt instrument interest percentage	4.20%
Bank Term Loan maturing in May 2018 [Member]
Debt Instrument [Line Items]
Debt instrument maturity year	Jul. 31, 2020
Five Year Senior Unsecured Notes At6.75 Maturing October152019 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross			99.0
Debt instrument maturity year	Oct. 01, 2019
Debt instrument interest percentage	6.75%
Senior Unsecured Bonds at 7.25% maturing in 2021 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 380.0	$ 780.0	780.0
Debt instrument maturity year	Oct. 01, 2021
Debt instrument interest percentage	7.25%
4.35% Senior Notes due 2029 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 400.0
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 maturity year	Sep. 01, 2031
Debt instrument interest percentage	8.125%
Minimum [Member] \| Term Loan Maturing 2022 (DPL) [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage Rate Range, Minimum (Deprecated 2016-01-31)	3.57%		4.00%
Minimum [Member] \| Tax-exempt First Mortgage Bonds - rates from: 2.49% - 2.93% (a) and 1.29% - 1.42% (b)
Debt Instrument [Line Items]
Debt instrument interest percentage	2.49%		1.29%
Minimum [Member] \| Bank Term Loan maturing in May 2018 [Member]
Debt Instrument [Line Items]
Debt instrument interest percentage	3.02%		2.67%
Maximum [Member] \| Term Loan Maturing 2022 (DPL) [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage Rate Range, Minimum (Deprecated 2016-01-31)	4.82%		4.60%
Maximum [Member] \| Tax-exempt First Mortgage Bonds - rates from: 2.49% - 2.93% (a) and 1.29% - 1.42% (b)
Debt Instrument [Line Items]
Debt instrument interest percentage	2.93%		1.42%
Maximum [Member] \| Bank Term Loan maturing in May 2018 [Member]
Debt Instrument [Line Items]
Debt instrument interest percentage	4.10%		3.02%
Debt [Member]
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations, Including Current Maturities	$ 1,363.1		$ 1,475.9