Maximum credit available.

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- Definition

Percentage Of Liens Of Companies Consolidated Asset

+ References

No definition available.

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- Definition

Weighted Average Interest Rate Of Commercial Paper

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Publisher FASB

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-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13(2))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Subparagraph a(3)

-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph 2

-Article 9

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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
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- Definition

Description of the conditions for borrowing under the credit facility including the nature of any restrictions.

+ 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))

-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 19, 22

-Article 5

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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Balance Type:	na
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- 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

+ Details

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- Definition

Carrying value as of the balance sheet date of portion of long-term loans payable due within one year or the 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 210.5-02.20)

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

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Balance Type:	credit
Period Type:	instant

- Definition

Indebtedness divided by net capital.

+ References

No definition available.

+ Details

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Short-Term Borrowing - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Oct. 31, 2011
Short-term Debt [Line Items]
Credit facility expiry date	Oct. 31, 2017
Commercial paper, outstanding	$ 800,000,000us-gaap_CommercialPaper	$ 1,451,000,000us-gaap_CommercialPaper
Weighted average interest rate	0.40%	0.20%
Letters of credit outstanding under the Credit Agreement	11,000,000	26,000,000
Loans outstanding under credit agreement	0us-gaap_LoansPayableCurrent	0us-gaap_LoansPayableCurrent
Line of credit facility, covenant terms	Ratio of consolidated debt to consolidated total capital of 0.65 to 1 (at December 31, 2014 this ratio was 0.51 to 1 for Con Edison and CECONY); having liens on its assets in an aggregate amount exceeding five percent of its consolidated total capital, subject to certain exceptions; and the failure, following any applicable notice period, to meet certain other customary covenants.
Ratio of consolidated debt to consolidated total capital	0.51
Minimum percentage of liens on assets	5.00%
October 2016 [Member]
Short-term Debt [Line Items]
Current amount available	1,000,000,000
Maximum [Member]
Short-term Debt [Line Items]
Ratio of consolidated debt to consolidated total capital			0.65
Letters of Credit [Member] \| October 2016 [Member]
Short-term Debt [Line Items]
Maximum credit available	2,250,000,000
Maximum borrowing capacity	1,200,000,000
Letters of Credit [Member] \| October 2017 [Member]
Short-term Debt [Line Items]
Maximum credit available	2,100,000,000
CECONY [Member]
Short-term Debt [Line Items]
Commercial paper, outstanding	450,000,000	1,210,000,000
Weighted average interest rate	0.40%	0.20%
Letters of credit outstanding under the Credit Agreement	$ 11,000,000	$ 11,000,000
Ratio of consolidated debt to consolidated total capital	0.51