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

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

+ References

No definition available.

+ Details

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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
-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 SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 9

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Period Type:	instant

- 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.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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=56944662&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Debt (Narrative) (Details) $ in Millions			9 Months Ended
Debt (Narrative) (Details) $ in Millions	Oct. 17, 2016 USD ($)	Feb. 05, 2016 USD ($)	Sep. 30, 2016 USD ($) fiscal_quarter debt_covenant	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Retirement of long-term debt			$ 520.8	$ 474.5
THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Retirement of long-term debt			445.3	$ 314.5
Senior unsecured due in October 2016 - 6.5% [Member]
Debt Instrument [Line Items]
Debt called/redeemed		$ 73.0
Term loan outstanding			$ 57.0		$ 130.0
Debt instrument interest percentage			6.50%		6.50%
Debt Instrument, Basis Spread on Variable Rate		0.50%
Retirement of long-term debt		$ 75.4
One Point Nine Percentage Of First Mortgage Bonds Maturing September Two Thousand Sixteen [Member]
Debt Instrument [Line Items]
Term loan outstanding					$ 445.0
Debt instrument interest percentage			1.875%		1.875%
One Point Nine Percentage Of First Mortgage Bonds Maturing September Two Thousand Sixteen [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Term loan outstanding			$ 0.0		$ 445.0
Debt instrument interest percentage			1.875%		1.875%
Term Loan Maturing 2022 [Member]
Debt Instrument [Line Items]
Term loan outstanding			$ 445.0		$ 0.0
Debt Instrument, Basis Spread on Variable Rate			3.25%
Term Loan Maturing 2022 [Member] \| THE DAYTON POWER AND LIGHT COMPANY [Member]
Debt Instrument [Line Items]
Term loan outstanding			$ 445.0		$ 0.0
Debt Instrument, Basis Spread on Variable Rate			3.25%
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] \| Senior unsecured due in October 2016 - 6.5% [Member]
Debt Instrument [Line Items]
Debt called/redeemed	$ 57.0