Retirement Plans and Other Retiree Benefits (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
United States Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Voluntary benefit plan contribution	$ 0	$ 0
Components of net periodic benefit cost
Service cost	0	0
Interest cost	25	25
Expected return on plan assets	(29)	(27)
Amortization of transition and prior service costs (credits)	0	0
Amortization of actuarial loss (gain)	12	8
Net periodic benefit cost	8	6
International Pension Benefits [Member]
Components of net periodic benefit cost
Service cost	5	5
Interest cost	8	9
Expected return on plan assets	(8)	(7)
Amortization of transition and prior service costs (credits)	0	1
Amortization of actuarial loss (gain)	3	1
Net periodic benefit cost	8	9
Other Retiree Benefits [Member]
Components of net periodic benefit cost
Service cost	4	3
Interest cost	11	10
Expected return on plan assets	(1)	0
Amortization of transition and prior service costs (credits)	0	0
Amortization of actuarial loss (gain)	7	4
Net periodic benefit cost	$ 21	$ 17