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Long Term Debt Maturities Repayments Of Principal, Total

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Long Term Debt Range Adjusted To Fair Value at Merger Start

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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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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.

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

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

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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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Debt (Long-term Debt) (Details) - USD ($) $ in Millions	12 Months Ended
Debt (Long-term Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Oct. 01, 2017
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	$ 103.6
Disposal Group, Including Discontinued Operations, Long-Term Debt	0.0	$ (0.3)
Unamortized Deferred Financing Costs	(4.3)	(6.8)
Debt Instrument, Unamortized Discount (Premium), Net	(0.5)	(0.6)
Total long-term debt at subsidary	586.1	646.6
Less: current portion	(103.6)	(4.6)
Long-term debt, net of current portion	$ 1,372.3	1,700.2
Debt maturity date, earliest	2019
Debt maturity date, latest	2061
Long-term Debt, Maturities, Repayments of Principal in Year Two	$ 144.7
Long-term Debt, Maturities, Repayments of Principal in Year Three	784.7
Long-term Debt, Maturities, Repayments of Principal in Year Four	422.8
Long-term Debt, Maturities, Repayments of Principal in Year Five	0.2
Long-term Debt, Maturities, Repayments of Principal after Year Five	32.4
Total Maturities Before Unamortized Adjustments	1,488.4
Unamortized adjustments to market value from purchase accounting	1.9
Unamortized Deferred Financing Costs, Consolidated	(10.6)
Long Term Debt Maturities Repayments Of Principal, Total	1,475.9
THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	4.6
Unamortized Deferred Financing Costs		(9.8)
Unamortized Deferred Financing Costs (Subsidiary)	(6.3)	(9.8)
Debt Instrument, Unamortized Discount	(1.4)	(2.0)
Debt Instrument, Unamortized Discount (Premium), Net	(1.4)	(2.0)
Less: current portion	(4.6)	(4.6)
Long-term debt, net of current portion	581.5	642.0
Long-term Debt, Maturities, Repayments of Principal in Year Two	144.7
Long-term Debt, Maturities, Repayments of Principal in Year Three	4.7
Long-term Debt, Maturities, Repayments of Principal in Year Four	422.8
Long-term Debt, Maturities, Repayments of Principal in Year Five	0.2
Long-term Debt, Maturities, Repayments of Principal after Year Five	16.8
Total Maturities Before Unamortized Adjustments	593.8
Unamortized Deferred Financing Costs, Consolidated	(6.3)
Long Term Debt Maturities Repayments Of Principal, Total	586.1
Term Loan Maturing 2022 (DPL) [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 436.1	440.6
Debt instrument maturity year	Aug. 24, 2022
Term Loan Maturing 2022 (DPL) [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 436.1	440.6
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	200.0
Debt instrument maturity year	Aug. 01, 2020
Tax-exempt First Mortgage Bonds - rates from: 2.49% - 2.93% (a) and 1.29% - 1.42% (b) \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 140.0	200.0
Debt instrument maturity year	Aug. 01, 2020
U.S. Government note maturing in 2061 - 4.20% [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 17.7	17.8
Debt instrument maturity year	Feb. 01, 2061
Debt instrument interest percentage	4.20%
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	$ 17.7	17.8
Debt instrument maturity year	Feb. 01, 2061
Debt instrument interest percentage	4.20%
Bank Term Loan Maturing July 2020 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 0.0	70.0
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	200.0
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	$ 780.0	780.0
Debt instrument maturity year	Oct. 01, 2021
Debt instrument interest percentage	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 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] \| Term Loan Maturing 2022 (DPL) [Member] \| THE DAYTON POWER AND LIGHT COMPANY [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] \| Tax-exempt First Mortgage Bonds - rates from: 2.49% - 2.93% (a) and 1.29% - 1.42% (b) \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Debt instrument interest percentage	2.49%
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] \| Term Loan Maturing 2022 (DPL) [Member] \| THE DAYTON POWER AND LIGHT COMPANY [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] \| Tax-exempt First Mortgage Bonds - rates from: 2.49% - 2.93% (a) and 1.29% - 1.42% (b) \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Debt instrument interest percentage	2.93%
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	$ 1,475.9	$ 1,704.8
Debt [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations, Including Current Maturities	$ 586.1	$ 646.6
Generation [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Disposal Group, Including Discontinued Operations, Long-Term Debt			$ (0.3)