Short-Term Borrowings And Long-Term Debt (Credit Facilities) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended			9 Months Ended	12 Months Ended	9 Months Ended		12 Months Ended	9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Texas Competitive Electric Holdings Company LLC [Member]	Sep. 30, 2013 Texas Competitive Electric Holdings Company LLC [Member] Revolving Credit Facility [Member] Revolving Credit Facility maturing October 2013 [Member]	Dec. 31, 2010 Texas Competitive Electric Holdings Company LLC [Member] Revolving Credit Facility [Member] Revolving Credit Facility maturing October 2013 [Member]	Sep. 30, 2013 Texas Competitive Electric Holdings Company LLC [Member] Revolving Credit Facility [Member] Revolving Credit Facility maturing October 2016 [Member]		Dec. 31, 2010 Texas Competitive Electric Holdings Company LLC [Member] Revolving Credit Facility [Member] Revolving Credit Facility maturing October 2016 [Member]	Sep. 30, 2013 Texas Competitive Electric Holdings Company LLC [Member] Letter of Credit [Member] Letter of Credit Facility maturing October 2017 [Member]		Sep. 30, 2013 Texas Competitive Electric Holdings Company LLC [Member] Letter of Credit [Member] Letter of Credit Facility maturing October 2014 [Member]		Dec. 31, 2012 Texas Competitive Electric Holdings Company LLC [Member] Letter of Credit [Member] Letter of Credit Facility maturing October 2014 [Member]		Sep. 30, 2013 Texas Competitive Electric Holdings Company LLC [Member] Line of Credit [Member]	Jan. 31, 2013 Subsequent Event [Member] Texas Competitive Electric Holdings Company LLC [Member] Revolving Credit Facility [Member]	Jan. 31, 2013 Subsequent Event [Member] Texas Competitive Electric Holdings Company LLC [Member] Revolving Credit Facility [Member] Revolving Credit Facility maturing October 2013 Extended to October 2016 [Member]
Credit Facilities [Line Items]
Facility Limit			$ 3,116			$ 2,054	[1]		$ 1,062	[2]						$ 2,054	$ 645
Letters of Credit			0			0	[1]		0	[2]
Cash Borrowings			3,116			2,054	[1]		1,062	[2]
Availability			0			0	[1]		0	[2]
Basis Spread on LIBOR Rate (as a percent)				4.50%		4.50%					3.50%
Per annum rate, commitment fee of average daily unused portion of credit facility (as a percent)					1.00%	1.00%		1.00%
Long-term debt, gross											42	[3]	42	[3]	22,635
Restricted cash	947	947							947
Reduction in restricted cash related to letter of credit drawn related to office building financing									(115)
Restricted Cash, Amount supported in letters of credit outstanding									776
Resticted cash, additional letters of credit that can be supported									171
Debt Issuance Fee Paid By Issuance Of Debt	$ 340

[1] Facility used for borrowings for general corporate purposes. Borrowings are classified as short-term borrowings. At September 30, 2013, borrowings under the facility bear interest at LIBOR plus 4.50%, and a commitment fee is payable quarterly in arrears at a rate per annum equal to 1.00% of the average daily unused portion of the facility. In January 2013, commitments previously maturing in 2013 were extended to 2016 as discussed below.

[2] Facility, $42 million of which matures in October 2014, used for issuing letters of credit for general corporate purposes, including, but not limited to, providing collateral support under hedging arrangements and other commodity transactions that are not secured by a first-lien interest in the assets of TCEH. The borrowings under this facility have been recorded by TCEH as restricted cash that supports issuances of letters of credit and are classified as long-term debt. At September 30, 2013, the restricted cash totaled $947 million, after reduction for a $115 million letter of credit drawn in 2009 related to an office building financing. At September 30, 2013, the restricted cash supports $776 million in letters of credit outstanding, leaving $171 million in available letter of credit capacity.

[3] Interest rates in effect at September 30, 2013.