Segment Information (Schedule Of Revenue from External Customers Attributed to Foreign Countries by Geographic Area) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	$ 22,302	$ 20,008	$ 20,005	$ 19,383	$ 19,555	$ 17,727	$ 16,543	$ 14,910	$ 81,698	$ 68,735	$ 64,306
Asia, Other Than China
Revenues from External Customers and Long-Lived Assets [Line Items]
Total non-U.S. revenues									10,390	7,438	7,288
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Total non-U.S. revenues									6,086	4,779	3,109
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Total non-U.S. revenues									10,269	9,850	7,872
Middle East
Revenues from External Customers and Long-Lived Assets [Line Items]
Total non-U.S. revenues									10,285	5,477	3,685
Oceania
Revenues from External Customers and Long-Lived Assets [Line Items]
Total non-U.S. revenues									2,043	3,067	1,707
Africa
Revenues from External Customers and Long-Lived Assets [Line Items]
Total non-U.S. revenues									1,282	1,759	956
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Total non-U.S. revenues									586	618	612
Latin America, Caribbean And Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Total non-U.S. revenues									3,555	1,356	930
Non-U.S.
Revenues from External Customers and Long-Lived Assets [Line Items]
Total non-U.S. revenues									44,496	34,344	26,159
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
United States revenues									$ 37,202	$ 34,391	$ 38,147