Disposal Group, Including Discontinued Operations, Long-Term Debt

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- Definition

Long Term Debt Maturities Repayments Of Principal, Total

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- Definition

Total Maturities Before Unamortized Adjustments

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- Definition

Unamortized Deferred Financing Costs

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- Definition

Unamortized Deferred Financing Costs, Consolidated

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- Definition

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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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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- Definition

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 Maturities) (Details) - THE DAYTON POWER AND LIGHT COMPANY [Member] - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017	Oct. 01, 2017
Debt Instrument [Line Items]
Unamortized Deferred Financing Costs, Consolidated		$ (6.3)
Current portion - long-term debt		4.6
Long-term Debt, Maturities, Repayments of Principal in Year Two		144.7
2018		4.7
2019		422.8
2020		0.2
Thereafter		16.8
Total Maturities		593.8
Debt Instrument, Unamortized Discount	$ (2.7)	(1.4)	$ (2.0)
Total long-term debt		586.1
Unamortized Deferred Financing Costs			(9.8)
Current portion - long-term debt	139.6	4.6	4.6
Long-term Debt, Excluding Current Maturities	434.6	581.5	642.0
Term Loan Maturing 2022 (DPL) [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		436.1	440.6
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	140.0	200.0
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	$ 17.6	17.7	17.8
Generation [Member]
Debt Instrument [Line Items]
Disposal Group, Including Discontinued Operations, Long-Term Debt				$ 0.3
Debt [Member]
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations, Including Current Maturities		$ 586.1	$ 646.6