Pension And Other Postretirement Benefits (Schedule Of Obligations And Funded Status) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of year	$ 10,339	[1]	$ 9,486	[1]
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	12,343
Service cost	165	[2]	148	[2]	139	[2]
Interest cost	678	[2]	682	[2]	682	[2]
Benefit obligation at end of year	13,526		12,343
Funded status	(3,215)	[3]	(2,892)	[3]
Less: Amounts attributed to joint venture partners	(34)		(26)
Net funded status	(3,181)		(2,866)
Noncurrent assets	109		84
Current liabilities	(29)		(27)
Noncurrent liabilities	(3,261)		(2,923)
Net amount recognized	(3,181)		(2,866)
Net actuarial loss	5,191		4,221
Prior service cost (benefit)	129		106
Total, before tax effect	5,320		4,327
Less: Amounts attributed to joint venture partners	46		36
Net amount recognized, before tax effect	5,274		4,291
Net actuarial loss (gain)	1,216		470
Amortization of accumulated net actuarial loss	(246)		(181)
Prior service cost (benefit)	42		42
Amortization of prior service (cost) benefit	(19)		(17)
Total, before tax effect	993		314
Less: Amounts attributed to joint venture partners	10		13
Net amount recognized, before tax effect	983		301
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	17	[4]	20	[4]	21	[4]
Interest cost	158	[4]	174	[4]	184	[4]
Funded status	(2,836)	[3]	(2,844)	[3]
Less: Amounts attributed to joint venture partners	(5)		(5)
Net funded status	(2,831)		(2,839)
Current liabilities	(248)		(224)
Noncurrent liabilities	(2,583)		(2,615)
Net amount recognized	(2,831)		(2,839)
Net actuarial loss	511		520
Prior service cost (benefit)	(92)		(108)
Total, before tax effect	419		412
Less: Amounts attributed to joint venture partners	(1)
Net amount recognized, before tax effect	420		412
Net actuarial loss (gain)	17		(78)
Amortization of accumulated net actuarial loss	(26)		(33)
Prior service cost (benefit)	(1)		9
Amortization of prior service (cost) benefit	17		15
Total, before tax effect	7		(87)
Less: Amounts attributed to joint venture partners	(1)		(2)
Net amount recognized, before tax effect	8		(85)
Domestic Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at end of year	10,702		9,791
Fair value of plan assets at end of year	7,988		7,242
Funded status	(2,714)		(2,549)
Change In Benefit Obligation [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	12,343	[3]	11,638
Service cost	183		152
Interest cost	687		691
Amendments	40		41
Actuarial losses (gains)	1,163		544
Settlements	(32)		(8)
Curtailments	(7)		(10)
Foreign currency translation impact	(38)		94
Benefit obligation at end of year	13,526	[3]	12,343	[3]
Benefits paid	(813)		(799)
Change In Benefit Obligation [Member] | Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	2,902	[3]	3,038
Service cost	17		21
Interest cost	159		175
Amendments	(1)		8
Actuarial losses (gains)	17		(75)
Settlements			(6)
Medicare Part D subsidy receipts	25		26
Foreign currency translation impact			2
Benefit obligation at end of year	2,844	[3]	2,902	[3]
Benefits paid	(275)		(287)
Change In Plan Assets [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	9,451	[3]	8,529
Actual return on plan assets	783		941
Employer contributions	945		718
Participants' contributions	35		30
Benefits paid	(805)		(800)
Administrative expenses	(38)		(39)
Settlements	(34)		(8)
Foreign currency translation impact	(26)		80
Fair value of plan assets at end of year	10,311	[3]	9,451	[3]
Change In Plan Assets [Member] | Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	58	[3]	111
Actual return on plan assets	2		8
Benefits paid	(52)		(61)
Fair value of plan assets at end of year	$ 8	[3]	$ 58	[3]

[1] As of December 31, 2011, the total fair value of pension and other postretirement plans' assets excludes a net payable of $20, which represents securities purchased not yet settled less interest and dividends earned on various investments. As of December 31, 2010, the total fair value of pension and other postretirement plans' assets excludes a net receivable of $23, which represents interest and dividends earned on various investments less securities purchased not yet settled.

[2] In 2011, 2010, and 2009, net periodic benefit cost for U.S pension plans was $190, $155, and $135, respectively.

[3] At December 31, 2011, the benefit obligation, fair value of plan assets, and funded status for U.S. pension plans were $10,702, $7,988, and $(2,714), respectively. At December 31, 2010, the benefit obligation, fair value of plan assets, and funded status for U.S. pension plans were $9,791, $7,242, and $(2,549), respectively.

[4] In 2011, 2010, and 2009, net periodic benefit cost for other postretirement benefits reflects a reduction of $43, $39, and $42, respectively, related to the recognition of the federal subsidy awarded under Medicare Part D.