Additional principal amount of senior notes to be raised

No definition available.

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- Definition

Letter Of Credit Sublimit

+ References

No definition available.

+ Details

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- Definition

Percentage amount term loan amortizes in first year

+ 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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

Reference 2: 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)

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-Number 210

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-Paragraph 22

-Article 5

Reference 4: 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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Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: 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(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: 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(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: 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(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Net increase or decrease in the carrying amount of the credit facility for the period for reasons other than accrued, but unpaid interest, additional borrowings, repayments, and forgiveness.

+ References

+ Details

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Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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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

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 210.5-02.19,20)

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-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 02

-Paragraph 19

-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ 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 22

-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(f))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph f

-Article 4

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

+ Details

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Balance Type:	debit
Period Type:	duration

- 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

+ 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 22

-Article 5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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Namespace Prefix:
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- Details

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Debt Obligations (Narrative) (Details) (USD $)	0 Months Ended	3 Months Ended		12 Months Ended	0 Months Ended	12 Months Ended	1 Months Ended
Debt Obligations (Narrative) (Details) (USD $)	Oct. 03, 2011	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	May 10, 2013	Dec. 31, 2013	Oct. 31, 2014	Dec. 04, 2008	Oct. 06, 2014	Sep. 06, 2014	Mar. 01, 2011	Sep. 19, 2013
Additional principal amount of senior notes to be raised	$ 1,250,000,000
Withdrawals from revolving credit facilities		15,000,000us-gaap_ProceedsFromLinesOfCredit	65,000,000us-gaap_ProceedsFromLinesOfCredit
Letters of credit outstanding				2,300,000
Collateralized debt								100,000,000us-gaap_SecuredLongTermDebt
Line of Credit Facility, Remaining Borrowing Capacity				97,700,000
Long-term Debt, Gross				2,139,600,000us-gaap_DebtInstrumentCarryingAmount		2,284,200,000us-gaap_DebtInstrumentCarryingAmount
Current portion - long-term debt		30,100,000us-gaap_LongTermDebtCurrent		20,100,000us-gaap_LongTermDebtCurrent		10,200,000us-gaap_LongTermDebtCurrent
Maximum [Member]
Debt instrument maturity date				Dec. 31, 2061
Minimum [Member]
Debt instrument maturity date				Dec. 31, 2016
DPL [Member] \| Credit Facility [Member]
Letters of credit outstanding		2,300,000
Line of Credit Facility, Remaining Borrowing Capacity		97,700,000
Senior Unsecured notes maturing October 2019 at 6.75% [Member]
Debt Instrument, Face Amount									200,000,000
Debt instrument interest percentage									6.75%
Senior Unsecured Notes At 6.50 Maturing On October 15 2016[Member]
Debt Instrument, Face Amount										280,000,000
Senior Unsecured Notes At 6.50 Maturing On October 15 2016[Member] \| Tender offer [Member]
Debt Instrument, Face Amount									300,000,000
U.S. Government note maturing in February 2061 - 4.20% [Member]
Debt Instrument, Maturity Date Range, End		Feb. 01, 2061		Feb. 01, 2061
Long-term Debt, Gross		18,100,000		18,100,000		18,300,000					18,700,000
Current portion - long-term debt		100,000		100,000
Debt instrument interest percentage		4.20%		4.20%							4.20%
Revolving Credit Agreement with Bank Group [Member]
Unsecured revolving credit agreement					100,000,000
Increase/decrease additional facility					100,000,000
Letter of credit sublimit					100,000,000
Revolving Credit Agreeement with Bank Group Expiring 2018 [Member]
Debt instrument maturity date		May 10, 2018
Unsecured revolving credit agreement					300,000,000
Increase/decrease additional facility					50,000,000
Letter of credit sublimit					100,000,000
Letters of credit outstanding				700,000
Line of Credit Facility, Remaining Borrowing Capacity				299,300,000
Revolving Credit Agreeement with Bank Group Expiring 2018 [Member] \| DP&L [Member]
Unsecured revolving credit agreement					300,000,000
Increase/decrease additional facility					100,000,000
Letter of credit sublimit					100,000,000
Letters of credit outstanding		1,400,000
Line of Credit Facility, Remaining Borrowing Capacity		298,600,000
Revolving Credit Agreeement with Bank Group Expiring 2018 [Member] \| DPL [Member]
Debt instrument maturity date					May 10, 2018
Unsecured revolving credit agreement					100,000,000
Increase/decrease additional facility					50,000,000
Letter of credit sublimit					100,000,000
Senior Unsecured Notes at 6.50% maturing on October 15, 2016 [Member]
Additional principal amount of senior notes to be raised	450,000,000
Debt Instrument, Maturity Date Range, End		Oct. 01, 2016		Oct. 01, 2016
Long-term Debt, Gross		130,000,000		130,000,000		430,000,000
Repayments of debt						20,000,000
Debt instrument interest percentage	6.50%	6.50%		6.50%		6.50%
Ten Year Senior Unsecured Notes at 7.25% maturing at October 15, 2021 [Member]
Additional principal amount of senior notes to be raised	800,000,000
Debt Instrument, Maturity Date Range, End		Oct. 01, 2021		Oct. 01, 2021
Long-term Debt, Gross		780,000,000		780,000,000		780,000,000
Repayments of debt						20,000,000
Debt instrument interest percentage	7.25%	7.25%		7.25%		7.25%
Unsecured Term Loan Agreement [Member]
Long-term Debt, Gross					200,000,000
Term Loan Amortization Year 1					5.00%
Repayments of debt					200,000,000
First Mortgage Bonds Maturing in September 2016 - 1.875%
Debt Instrument, Maturity Date Range, End		Sep. 01, 2016		Sep. 01, 2016
Long-term Debt, Gross		445,000,000		445,000,000		445,000,000						445,000,000
Debt instrument interest percentage		1.875%		1.875%
Note to DPL Capital Trust II Maturing in September 2031 - 8.125% [Member]
Debt Instrument, Maturity Date Range, End		Sep. 01, 2031		Sep. 01, 2031
Long-term Debt, Gross		15,600,000		15,600,000		20,600,000
Repayments of debt							5,000,000
Debt instrument interest percentage		8.125%		8.125%
Pollution control series maturing in November 2040 - variable rates: 0.04% - 0.26% and 0.06% - 0.32% [Member]
Debt Instrument, Maturity Date Range, End		Nov. 01, 2040		Nov. 01, 2040
Long-term Debt, Gross		100,000,000		100,000,000		100,000,000
Debt instrument interest percentage		0.02%
Bank Term Loan maturing in May 2018 [Member]
Debt Instrument, Maturity Date Range, End		May 01, 2018		May 01, 2018
Loans Payable, Noncurrent				160,000,000
Long-term Debt, Gross		130,000,000		140,000,000		180,000,000
Current portion - long-term debt		$ 30,000,000		20,000,000		$ 10,000,000
Debt instrument interest percentage				2.41%