Changes in Accumulated Other Comprehensive Losses (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013	Jun. 30, 2014		Jun. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period				$ (3,579)	[1]
Components of Other Comprehensive Income (Loss):
Before Reclassifications				(66)	[1]
Reclassifications				148	[1],[2]
Other Comprehensive Gain, Net of Tax	37		191	82	[1]	291
Balance at end of period	(3,497)	[1]		(3,497)	[1]
Income tax expense	3,337		3,185	6,744		7,229
Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period				(23)	[1]
Components of Other Comprehensive Income (Loss):
Before Reclassifications				(30)	[1]
Reclassifications				0	[1],[2]
Other Comprehensive Gain, Net of Tax				(30)	[1]
Balance at end of period	(53)	[1]		(53)	[1]
Unrealized Holding Gains (Losses) on Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period				(6)	[1]
Components of Other Comprehensive Income (Loss):
Before Reclassifications				8	[1]
Reclassifications				0	[1],[2]
Other Comprehensive Gain, Net of Tax				8	[1]
Balance at end of period	2	[1]		2	[1]
Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period				52	[1]
Components of Other Comprehensive Income (Loss):
Before Reclassifications				(53)	[1]
Reclassifications				(1)	[1],[2]
Other Comprehensive Gain, Net of Tax				(54)	[1]
Balance at end of period	(2)	[1]		(2)	[1]
Defined Benefit Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period				(3,602)	[1]
Components of Other Comprehensive Income (Loss):
Before Reclassifications				9	[1]
Reclassifications				149	[1],[2]
Other Comprehensive Gain, Net of Tax				158	[1]
Balance at end of period	(3,444)	[1]		(3,444)	[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				238
Income tax expense				$ 89

[1] All amounts are net of tax.

[2] Refer to Note 9, Employee Benefits for reclassified components totaling $238 million that are included in employee benefit costs for the six months ending June 30, 2014. Related income taxes for the same period, totaling $89 million, are reflected in Income Tax Expense on the Consolidated Statement of Income. All other reclassified amounts were insignificant.