Benefit Plans (Movements in Other Comprehensive Earnings/Losses) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss, Amortization	$ 340	$ 281	$ 226
Prior service cost/credit, Amortization	(35)	(35)	(7)
Net loss, Other expense (income)	6	21
Prior service cost/credit, Other expense (income)		(26)
Deferred income taxes	(120)	(93)	(85)
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, Net of Tax	191	148	134
Prior service cost/credit, Other movements during the year	(9)		266
Net loss, Other movements during the year	1,568	(815)	(900)
Deferred income taxes, Other movements during the year	(609)	315	249
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments, Net of Tax	950	(500)	(385)
Total movements in other comprehensive earnings/losses	1,141	(352)	(251)
Pension [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss, Amortization	271	224	171
Prior service cost/credit, Amortization	10	10	14
Net loss, Other expense (income)	6	21
Prior service cost/credit, Other expense (income)		0
Deferred income taxes	(111)	(99)	(72)
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, Net of Tax	176	156	113
Prior service cost/credit, Other movements during the year	(7)		2
Net loss, Other movements during the year	1,218	(643)	(672)
Deferred income taxes, Other movements during the year	(470)	249	262
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments, Net of Tax	741	(394)	(408)
Total movements in other comprehensive earnings/losses	917	(238)	(295)
Postretirement Benefit Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss, Amortization	51	40	39
Prior service cost/credit, Amortization	(45)	(45)	(21)
Net loss, Other expense (income)	0	0
Prior service cost/credit, Other expense (income)		(26)
Deferred income taxes	(2)	12	(7)
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, Net of Tax	4	(19)	11
Prior service cost/credit, Other movements during the year	(2)		264
Net loss, Other movements during the year	327	(161)	(188)
Deferred income taxes, Other movements during the year	(129)	63	(27)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments, Net of Tax	196	(98)	49
Total movements in other comprehensive earnings/losses	200	(117)	60
Postemployment Benefit Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss, Amortization	18	17	16
Prior service cost/credit, Amortization	0	0	0
Net loss, Other expense (income)	0	0
Prior service cost/credit, Other expense (income)		0
Deferred income taxes	(7)	(6)	(6)
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, Net of Tax	11	11	10
Prior service cost/credit, Other movements during the year	0		0
Net loss, Other movements during the year	23	(11)	(40)
Deferred income taxes, Other movements during the year	(10)	3	14
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments, Net of Tax	13	(8)	(26)
Total movements in other comprehensive earnings/losses	$ 24	$ 3	$ (16)