Segment Information (Schedule Of Revenue from External Customers Attributed to Foreign Countries by Geographic Area) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	$ 23,573	$ 25,849	$ 24,543	$ 22,149	$ 24,468	$ 23,784	$ 22,045	$ 20,465	$ 96,114	$ 90,762	$ 86,623
Non-U.S. [member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues									56,827	52,920	49,031
Asia, Other Than China [member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues									13,433	11,900	12,200
Europe [member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues									12,248	11,898	10,622
China [member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues									12,556	11,029	10,555
Middle East [member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues									10,846	9,243	9,165
Oceania [member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues									2,601	1,757	1,657
Canada [member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues									1,870	1,901	1,486
Africa [member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues									1,398	2,596	621
Latin America, Caribbean And Other [member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues									1,875	2,596	2,725
United States [member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues									$ 39,287	$ 37,842	$ 37,592