Debt Instrument Redemption Percentage Maximum

No definition available.

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- Definition

Debt Instrument Redemption Price Percentage Of Principal Amount Plus Premium And Accrued Interest

+ References

No definition available.

+ Details

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Namespace Prefix:	efh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Registration Default, if not filed and declared effective after original issue date, days

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Debt Instrument, Registration Default, if not filed and declared effective after original issue date, first quarter annual interest rate

+ References

No definition available.

+ Details

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Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Registration Default, if not filed and declared effective after original issue date, variable interest rate increase after initial increase

+ References

No definition available.

+ Details

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Namespace Prefix:	efh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Registration Default, if not filed and declared effective after original issue date, variable interest rate increase for quarter

+ References

No definition available.

+ Details

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Namespace Prefix:	efh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Senior Notes Redemption Price Expressed As Percentage Of Principal Amount Redeemed, Plus Accrued Interest

+ References

No definition available.

+ Details

Name:	efh_SeniorNotesRedemptionPriceExpressedAsPercentageOfPrincipalAmountRedeemedPlusAccruedInterest
Namespace Prefix:	efh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Senior Notes Redemption Price Percentage Of Principal

+ References

No definition available.

+ Details

Name:	efh_SeniorNotesRedemptionPricePercentageOfPrincipal
Namespace Prefix:	efh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents disclosure of the total aggregate cash dividends paid to the entity by consolidated subsidiaries, by unconsolidated subsidiaries, and by 50% or less owned persons accounted for using the equity method.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph b

-Article 12

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 3

-Subparagraph (SX 210.12-04(b))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24072-122690

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 235

-Section S99

-Paragraph 2

-Subparagraph (SX 210.9-06)

-URI http://asc.fasb.org/extlink&oid=6882215&loc=d3e537971-122884

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 06

-Article 9

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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

- Details

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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 AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number APB14-1

-Paragraph 31

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

+ Details

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

- Definition

The amount of debt premium 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

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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

Long-Term Debt (Issuance of EFIH 11.75% Senior Secured Second Lien Notes) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended			1 Months Ended	9 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2012 Secured Debt [Member]	Dec. 31, 2011 Secured Debt [Member]	Feb. 29, 2012 Energy Future Intermediate Holding CO LLC [Member] Secured Debt [Member] 11.75% Senior Secured Second Lien Notes due March 1, 2022 [Member]	Sep. 30, 2012 Energy Future Intermediate Holding CO LLC [Member] Secured Debt [Member] 11.75% Senior Secured Second Lien Notes due March 1, 2022 [Member]	Aug. 31, 2012 Energy Future Intermediate Holding CO LLC [Member] Secured Debt [Member] 11.75% Senior Secured Second Lien Notes due March 1, 2022 [Member]	Sep. 30, 2012 Energy Future Intermediate Holding CO LLC [Member] Until March 1, 2015 [Member] Secured Debt [Member] 11.75% Senior Secured Second Lien Notes due March 1, 2022 [Member]	Sep. 30, 2012 Energy Future Intermediate Holding CO LLC [Member] Until March 1, 2017 [Member] Secured Debt [Member] 11.75% Senior Secured Second Lien Notes due March 1, 2022 [Member]	Sep. 30, 2012 Energy Future Intermediate Holding CO LLC [Member] March 1, 2017 and thereafter [Member] Secured Debt [Member] 11.75% Senior Secured Second Lien Notes due March 1, 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 1,150		$ 600
Debt Instrument, Unamortized Discount		11	0	12
Unamortized premium		14	0			14
Cash dividends paid to EFH	$ 950			$ 950
Debt Instrument Redemption Percentage Maximum							35.00%
Senior Notes Redemption Price Percentage Of Principal							111.75%
Debt Instrument Redemption Price Percentage Of Principal Amount Plus Premium And Accrued Interest								100.00%
Senior Notes Redemption Price Expressed As Percentage Of Principal Amount Redeemed, Plus Accrued Interest									101.00%
Debt Instrument, Registration Default, if not filed and declared effective after original issue date, days					365
Debt Instrument, Registration Default, if not filed and declared effective after original issue date, variable interest rate increase for quarter					0.25%
Debt Instrument, Registration Default, if not filed and declared effective after original issue date, first quarter annual interest rate					90
Debt Instrument, Registration Default, if not filed and declared effective after original issue date, variable interest rate increase after initial increase					0.50%