Debt And Related Expenses (Schedule Of Debt Instruments) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Debt Instrument [Line Items]
Commercial paper	$ 1,317		$ 3,189
Net discount on the other debentures and notes	(20)		(20)
Total debt	12,022		11,644
Less amount classified as short-term debt	4,066	[1]	3,189	[1]
Long-term debt	7,956		8,455
5.625% Due January 15, 2014 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	5.625%
Debt, maturity date	Jan. 15, 2014
Short-term debt	500		500
2.40% Due July 15, 2016 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	2.40%
Debt, maturity date	Jul. 15, 2016
Long term debt, gross	500		500
1.875% Due May 15, 2017 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	1.875%
Debt, maturity date	May 15, 2017
Long term debt, gross	750		750
8.25% Due July 1, 2018 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	8.25%
Debt, maturity date	Jul. 01, 2018
Long term debt, gross	125		125
6.30% Due January 15, 2019 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	6.30%
Debt, maturity date	Jan. 15, 2019
Long term debt, gross	700		700
4.00% Due July 15, 2021 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	4.00%
Debt, maturity date	Jul. 15, 2021
Long term debt, gross	500		500
3.25% Due May 15, 2022 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	3.25%
Debt, maturity date	May 15, 2022
Long term debt, gross	1,000		1,000
7.50% Due September 15, 2027 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	7.50%
Debt, maturity date	Sep. 15, 2027
Long term debt, gross	150		150
7.875% Due September 30, 2031 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	7.875%
Debt, maturity date	Sep. 30, 2031
Long term debt, gross	1,250		1,250
7.95% Due April 15, 2032 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	7.95%
Debt, maturity date	Apr. 15, 2032
Long term debt, gross	1,000		1,000
5.60% Due July 15, 2041 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	5.60%
Debt, maturity date	Jul. 15, 2041
Long term debt, gross	1,250		1,250
4.75% Due May 15, 2042 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	4.75%
Debt, maturity date	May 15, 2042
Long term debt, gross	750		750
Senior Notes For Acquisition of GeoSouthern [Member]
Debt Instrument [Line Items]
Short-term debt	2,250
GeoSouthern Intermediate Holdings, LLC [Member] | Floating Rate Due December 15, 2015 [Member]
Debt Instrument [Line Items]
Debt, maturity date	Dec. 15, 2015
Short-term debt	500
GeoSouthern Intermediate Holdings, LLC [Member] | Floating Rate Due December 15, 2016 [Member]
Debt Instrument [Line Items]
Debt, maturity date	Dec. 15, 2016
Short-term debt	350
GeoSouthern Intermediate Holdings, LLC [Member] | 1.20% Due December 15, 2016 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	1.20%
Debt, maturity date	Dec. 15, 2016
Short-term debt	650
GeoSouthern Intermediate Holdings, LLC [Member] | 2.25% Due December 15, 2018 [Member]
Debt Instrument [Line Items]
Debt interest rate, stated percentage	2.25%
Debt, maturity date	Dec. 15, 2018
Short-term debt	$ 750

[1] 2013 short-term debt consists of $2.25 billion of senior notes recently issued in conjunction with the planned GeoSouthern acquisition, $1.3 billion of commercial paper and $500 million of senior notes due January 15, 2014.