Changes in Accumulated Other Comprehensive Losses (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	$ (6,369)	[1]
Components of Other Comprehensive Income (Loss):
Before Reclassifications	2,265	[1]
Reclassifications	525	[1],[2]
Other Comprehensive Gain (Loss), Net of Tax	2,790	[1]	(347)		(1,556)
Balance at end of period	(3,579)	[1]	(6,369)	[1]
Income tax expense	14,308		19,996		20,626
Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	(65)	[1]
Components of Other Comprehensive Income (Loss):
Before Reclassifications	42	[1]
Reclassifications	0	[1],[2]
Other Comprehensive Gain (Loss), Net of Tax	42	[1]	23		17
Balance at end of period	(23)	[1]	(65)	[1]
Unrealized Holding Gains (Losses) on Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	1	[1]
Components of Other Comprehensive Income (Loss):
Before Reclassifications	(7)	[1]
Reclassifications	0	[1],[2]
Other Comprehensive Gain (Loss), Net of Tax	(7)	[1]	1		(11)
Balance at end of period	(6)	[1]	1	[1]
Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	125	[1]
Components of Other Comprehensive Income (Loss):
Before Reclassifications	(72)	[1]
Reclassifications	(1)	[1],[2]
Other Comprehensive Gain (Loss), Net of Tax	(73)	[1]	3		19
Balance at end of period	52	[1]	125	[1]
Defined Benefit Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	(6,430)	[1]
Components of Other Comprehensive Income (Loss):
Before Reclassifications	2,302	[1]
Reclassifications	526	[1],[2]
Other Comprehensive Gain (Loss), Net of Tax	2,828	[1]	(374)		(1,581)
Balance at end of period	(3,602)	[1]	(6,430)	[1]
Defined Benefit Plans [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Components of Other Comprehensive Income (Loss):
Employee benefits reclassification component, included in employee benefit costs	839
Income tax expense	$ 313

[1] All amounts are net of tax.

[2] Refer to Note 21, Employee Benefits for reclassified components totaling $839 that are included in employee benefit costs for the year ending December 31, 2013. Related income taxes for the same period, totaling $313, are reflected in Income Tax Expense on the Consolidated Statement of Income. All other reclassified amounts were insignificant.