Liabilities Subject to Compromise - Guarantees and Push Down of EFH Corp. Debt (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Debt Instrument [Line Items]
Debt Instrument, Percentage of Securities Guaranteed by and Push Down Debt	50.00%
Parent's payment of interest on pushed-down debt accounted for as a contribution of capital (Note 7)	$ 0	$ 21
Payment of Interest on Pushed-down Debt Accounted for as a Contribution of Capital		21
Push Down Debt [Member]
Debt Instrument [Line Items]
Long-term debt, gross	30
Push Down Debt [Member] | Energy Future Holdings Corp. [Member]
Debt Instrument [Line Items]
Percentage of principal plus unamortized premium of related party Merger-related debt guaranteed by parent company (as a percent)	50.00%	50.00%
Energy Future Intermediate Holding CO LLC [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument Principal Amount Guarantee Obligations Of Subsidiaries	60
Energy Future Intermediate Holding CO LLC [Member] | Senior Notes [Member] | 10.875% EFH Corp. Fixed Senior Notes due November 1, 2017 [Member] | Financial Guarantee [Member] | Subject to Push Down [Member]
Debt Instrument [Line Items]
Debt Instrument Principal Amount Guarantee Obligations Of Subsidiaries	33
Energy Future Intermediate Holding CO LLC [Member] | Senior Notes [Member] | 11.25/12.00% EFH Corp. Senior Toggle Notes due November 1, 2017 [Member] | Financial Guarantee [Member] | Subject to Push Down [Member]
Debt Instrument [Line Items]
Debt Instrument Principal Amount Guarantee Obligations Of Subsidiaries	$ 27