Liabilities Subject to Compromise - EFIH 11.25%/12.25% Senior Toggle Notes (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014		Dec. 31, 2013
Debt Instrument [Line Items]
Liabilities Subject To Compromise, Debt	$ 3,843
Secured Debt [Member]
Debt Instrument [Line Items]
Liabilities Subject To Compromise, Debt	3,846
Secured Debt [Member] | 10% Fixed Senior Secured First Lien Notes due December 1, 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Registration Default, if not filed and declared effective after original issue date, variable interest rate increase for first ninety days	0.25%
Long-term debt, gross			3,482
Liabilities Subject To Compromise, Debt	0	[1]
Secured Debt [Member] | 6.875% Fixed Senior Secured First Lien Notes due August 15, 2017 [Member]
Debt Instrument [Line Items]
Long-term debt, gross			503
Liabilities Subject To Compromise, Debt	0	[1]
Secured Debt [Member] | Senior Secured Second Lien 11.75% Notes due March 1, 2022 [Member]
Debt Instrument [Line Items]
Long-term debt, gross			1,750
Secured Debt [Member] | 11.25%/12.25% Senior Toggle Notes due December 1, 2018 [Member]
Debt Instrument [Line Items]
Long-term debt, gross			1,566
Until June 1, 2016 [Member] | Senior Notes [Member] | 11.25%/12.25% Senior Toggle Notes due December 1, 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Options to Pay Interest, Percentage Allowed in Cash	50.00%
Debt Instrument, Options to Pay Interest, Percentage Allowed in PIK Interest	50.00%
Energy Future Intermediate Holding CO LLC [Member] | Secured Debt [Member] | 10% Fixed Senior Secured First Lien Notes due December 1, 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Registration Default, if not filed and declared effective after original issue date, total variable interest rate increase after first ninety day period	0.25%
Energy Future Intermediate Holding CO LLC [Member] | Secured Debt [Member] | 6.875% Fixed Senior Secured First Lien Notes due August 15, 2017 [Member]
Debt Instrument [Line Items]
Debt Instrument, Registration Default, if not filed and declared effective after original issue date, variable interest rate increase for first ninety days	0.25%
Energy Future Intermediate Holding CO LLC [Member] | Secured Debt [Member] | Senior Secured Second Lien 11.75% Notes due March 1, 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Registration Default, if not filed and declared effective after original issue date, variable interest rate increase for first ninety days	0.25%
Liabilities Subject To Compromise, Debt	1,750
Energy Future Intermediate Holding CO LLC [Member] | Senior Notes [Member] | 11.25%/12.25% Senior Toggle Notes due December 1, 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Registration Default, if not filed and declared effective after original issue date, variable interest rate increase for first ninety days	0.25%
Liabilities Subject To Compromise, Debt	$ 1,566
Debt Instrument, Registration Default, if not filed and declared effective after original issue date, total variable interest rate increase after first ninety day period	0.25%

[1] The EFIH First Lien Notes were exchanged or settled in June 2014 (see Note 5).