Retirement Benefits (Net Periodic Pension Costs (Benefit)) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Amortization of:
Unrecognized prior service benefit	$ (50)	$ (43)	$ (16)
U.S. Pension Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0
Interest cost	370	352	349
Expected return on plan assets	(381)	(364)	(421)
Amortization of:
Unrecognized net loss	97	130	260
Unrecognized prior service benefit	0	0	0
Settlement/loss	1,883	0	0
Net periodic pension cost (benefit)	1,969	118	188
Non U.S. Pension Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	15	11	10
Interest cost	80	69	73
Expected return on plan assets	(90)	(77)	(77)
Amortization of:
Unrecognized net loss	12	13	22
Unrecognized prior service benefit	(7)	(6)	(3)
Settlement/loss	0	0	0
Net periodic pension cost (benefit)	10	10	25
Postretirement Health Care Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	2	2	3
Interest cost	10	11	16
Expected return on plan assets	(10)	(10)	(12)
Amortization of:
Unrecognized net loss	9	14	12
Unrecognized prior service benefit	(50)	(43)	(16)
Settlement/loss	0	0	0
Net periodic pension cost (benefit)	$ (39)	$ (26)	$ 3