Deferred Finance Costs, Net, Including Acquisition Adjustments

No definition available.

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- Definition

Long Term Debt Range Adjusted To Fair Value At Merger End

+ References

No definition available.

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- Definition

Long Term Debt Range Adjusted To Fair Value at Merger Start

+ References

No definition available.

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- Definition

Total Long-term Debt At Subsidiary With Purchase Accounting Adjustments

+ References

No definition available.

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 7

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 210
-SubTopic 10
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-Name Regulation S-X (SX)
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- Definition

When presenting a range of interest rates, the highest effective rate for funds borrowed under the debt agreement as of the balance sheet date.

+ References

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- Definition

When presenting a range of interest rates, the lowest effective rate for funds borrowed under the debt agreement as of the balance sheet date.

+ References

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- Definition

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

+ References

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- Definition

Maximum contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Minimum contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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- Definition

The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20, 22
-Article 5

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- Definition

Amount of long-term debt, after unamortized discount or premium, scheduled 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.

+ References

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). 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		3 Months Ended	12 Months Ended
Debt (Long-term Debt) (Details) - USD ($) $ in Millions	Feb. 05, 2016	Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Capital Lease Obligations		$ 0.4	$ 0.4
Unamortized deferred finance costs		(10.1)	(10.7)
Unamortized deferred finance costs		(8.4)	(8.8)
Unamortized debt discount and premiums, net		(0.8)	(0.6)
Total long-term debt at subsidiary		746.8	747.2
Total long-term debt		1,852.0	1,858.4
Less: current portion		(29.7)	(29.7)
Long-term debt		$ 1,822.3	1,828.7
Long-term debt, earliest maturities		2019
Long-term debt, latest maturities		2061
THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Capital Lease Obligations		$ 0.4	0.4
Unamortized deferred finance costs		(11.5)	(11.8)
Unamortized debt discount and premiums, net		(5.3)	(5.5)
Unamortized debt discount		(2.0)	(2.2)
Total long-term debt		748.7	749.4
Less: current portion		(4.7)	(4.7)
Long-term debt		$ 744.0	744.7
Long-term debt, earliest maturities		2020
Long-term debt, latest maturities		2061
Term Loan Maturing 2022 [Domain]
Debt Instrument [Line Items]
Debt instrument maturity year		Aug. 24, 2022
Term Loan Maturing 2022 [Domain] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Debt instrument maturity year		Aug. 24, 2022
Term Loan Maturing 2022 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 443.9	$ 445.0
Debt Instrument, Interest Rate, Effective Percentage Rate Range, Minimum		4.00%	4.00%
Debt instrument interest percentage maximum		4.00%
Debt Instrument, Interest Rate, Effective Percentage Rate Range, Maximum			4.00%
Term Loan Maturing 2022 [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 443.9	$ 445.0
Debt Instrument, Interest Rate, Effective Percentage Rate Range, Minimum		4.01%	4.00%
Debt instrument interest percentage maximum		4.04%
Debt Instrument, Interest Rate, Effective Percentage Rate Range, Maximum			4.01%
Pollution Control Series Maturing in September 2036 - 4.80% [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 100.0	$ 100.0
Debt instrument maturity year		Sep. 01, 2036
Debt instrument interest percentage		4.80%
Pollution Control Series Maturing in September 2036 - 4.80% [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 100.0	$ 100.0
Debt instrument maturity year		Sep. 01, 2036
Debt instrument interest percentage		4.80%
Pollution Control Series Maturing in August 2020 - 1.13% - 1.14% [Member]
Debt Instrument [Line Items]
Debt instrument maturity year		Aug. 01, 2020
Debt instrument interest percentage minimum			1.29%
Debt instrument interest percentage maximum			1.42%
Pollution Control Series Maturing in August 2020 - 1.13% - 1.14% [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 200.0	$ 200.0
Debt instrument maturity year		Aug. 01, 2020
Zero Point Two Three To Zero Point Two Nine And Zero Point One Six To Zero Point Three Six Percentage Of Bonds Maturing In November Two Thousand Forty [Member]
Debt Instrument [Line Items]
Debt instrument interest percentage minimum		1.52%
Debt instrument interest percentage maximum		1.53%
Zero Point Two Three To Zero Point Two Nine And Zero Point One Six To Zero Point Three Six Percentage Of Bonds Maturing In November Two Thousand Forty [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Debt instrument interest percentage minimum		1.52%	1.29%
Debt instrument interest percentage maximum		1.53%	1.42%
U.S. Government note maturing in February 2061 - 4.20% [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 17.9	$ 18.0
Debt instrument maturity year		Feb. 01, 2061
Debt instrument interest percentage		4.20%
U.S. Government note maturing in February 2061 - 4.20% [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 17.9	18.0
Debt instrument maturity year		Feb. 01, 2061
Debt instrument interest percentage		4.20%
Bank term loan due in July 2020 - rates from: 2.44% - 2.45% [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 118.8	$ 125.0
Debt instrument maturity year		Jul. 31, 2020
Debt instrument interest percentage minimum		3.02%	2.67%
Debt instrument interest percentage maximum		3.73%	3.02%
Senior unsecured due in October 2016 - 6.5% [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.50%
Senior unsecured due in October 2019 - 6.75% [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 200.0	$ 200.0
Debt instrument maturity year		Oct. 01, 2019
Debt instrument interest percentage		6.75%
Senior unsecured due in October 2021 - 7.25% [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 September 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%