Retirement Plans (Reconciliation Of The Change In AOCI For Defined-Benefit Retirement Plans) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Amortization of:
Change in AOCI, pretax	$ 1,149		$ 1,129		$ 878
Pension Benefits
Compensation And Retirement Disclosure Line Items
Net actuarial loss	1,241		1,189
Prior service cost	0		16
Amortization of:
Net actuarial loss from prior years	(287)		(173)
Prior service credit (cost)	42		40
Other	(5)	[1]	3	[1]
Change in AOCI, pretax	991		1,075
Other Postretirement Benefit Plans, Defined Benefit
Compensation And Retirement Disclosure Line Items
Net actuarial loss	177		61
Prior service cost	0		3
Amortization of:
Net actuarial loss from prior years	(10)		(4)
Prior service credit (cost)	(7)		(6)
Other	(2)	[1]	0	[1]
Change in AOCI, pretax	$ 158		$ 54

[1] Includes foreign exchange translation adjustments.