Debt Instrument, Debt Covenant, Debt to EBITDA Ratio, Number of Quarters

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Number of Financial Covenants

+ References

No definition available.

+ Details

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- Definition

After separation required compliance with the financial covenant, shall be suspended from 1/1/17 to 12/31/17 if during such time DP&L's LT indebtedness (as determined by the PUCO) is less than or equal to $750.0 million.

+ References

No definition available.

+ Details

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- Definition

Total Debt to Total Capitalization Ratio

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

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

+ References

+ Details

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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

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

+ Details

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Period Type:	instant

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

+ Details

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- Details

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- Details

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- Details

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Debt (Narrative) (Details)				9 Months Ended		12 Months Ended
Debt (Narrative) (Details)	Oct. 30, 2017 USD ($)	Aug. 07, 2017 USD ($)	Jun. 23, 2017 USD ($)	Sep. 30, 2017 USD ($) fiscal_quarter debt_covenant	Sep. 30, 2016 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Long-term Line of Credit				$ 50,000,000
Retirement of long-term debt				$ 122,100,000	$ 520,800,000
Total Debt to Total Capitalization Ratio				0.46
THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Line of Credit				$ 15,000,000
Long-term Debt, Gross				659,900,000
Retirement of long-term debt				$ 103,300,000	$ 445,300,000
Total Debt to Total Capitalization Ratio				0.46
Four Point Eight Zero Percentage Of Bonds Maturing In September Two Thousand Thirty Six [Member]
Debt Instrument [Line Items]
Extinguishment of Debt, Amount		$ 21,900,000	$ 8,100,000
Long-term Debt, Gross							$ 100,000,000
Debt instrument interest percentage				4.80%
Four Point Eight Zero Percentage Of Bonds Maturing In September Two Thousand Thirty Six [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Extinguishment of Debt, Amount		$ 21,900,000	$ 8,100,000
Long-term Debt, Gross				$ 0			100,000,000
Debt instrument interest percentage				4.80%
Term Loan Maturing 2022 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross				$ 441,700,000			445,000,000
Term Loan Maturing 2022 [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross				$ 441,700,000			$ 445,000,000
Revolving Credit Agreement and Standby Letters of Credit [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Number of financial covenants \| debt_covenant				2
Number of prior quarters included in EBITDA to interest calculation \| fiscal_quarter				4
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 EBITDA to interest calculation \| fiscal_quarter				4
Number of prior quarters included in debt to EBITDA ratio \| fiscal_quarter				4
Subsequent Event [Member]
Debt Instrument [Line Items]
Repayments of Debt	$ 70,000,000
Long Term Indebtedness, Less than or Equal to						$ 750,000,000.0
Subsequent Event [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Repayments of Debt	$ 70,000,000
Long Term Indebtedness, Less than or Equal to						$ 750,000,000.0