Pension and Postretirement Benefit Plans (Components of net periodic benefit cost and other information) (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
United States Qualified and Non-qualified Pension Benefits
Net periodic benefit cost (benefit)
Service cost	$ 60	$ 64
Interest cost	169	150
Expected return on plan assets	(261)	(261)
Amortization of transition (asset) obligation	0	0
Amortization of prior service cost (benefit)	1	1
Amortization of net actuarial (gain) loss	61	100
Net periodic benefit cost (benefit)	30	54
Settlements, curtailments, special termination benefits and other	0	0
Net periodic benefit cost (benefit) after settlements, curtailments, special termination benefits and other	30	54
International Qualified and Non-qualified Pension Benefits
Net periodic benefit cost (benefit)
Service cost	36	36
Interest cost	64	61
Expected return on plan assets	(79)	(75)
Amortization of transition (asset) obligation	0	(1)
Amortization of prior service cost (benefit)	(4)	(4)
Amortization of net actuarial (gain) loss	31	40
Net periodic benefit cost (benefit)	48	57
Settlements, curtailments, special termination benefits and other	0	0
Net periodic benefit cost (benefit) after settlements, curtailments, special termination benefits and other	48	57
Postretirement Benefits
Net periodic benefit cost (benefit)
Service cost	16	20
Interest cost	24	22
Expected return on plan assets	(22)	(22)
Amortization of transition (asset) obligation	0	0
Amortization of prior service cost (benefit)	(12)	(17)
Amortization of net actuarial (gain) loss	14	24
Net periodic benefit cost (benefit)	20	27
Settlements, curtailments, special termination benefits and other	0	0
Net periodic benefit cost (benefit) after settlements, curtailments, special termination benefits and other	$ 20	$ 27