Postretirement Benefit Plans (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Change in benefit obligation:
Benefit obligation at end of year	$ 930	$ 840
Change in plan assets:
Ending Balance	584	524
Funded (unfunded) status of the plans	(346)	(316)
Domestic defined benefit pension plans
Change in benefit obligation:
Benefit obligation at beginning of year	74	83
Service cost	2	3	3
Interest cost	3	3	3
Benefits paid	(3)	(3)
Actuarial (gain) loss	13	(8)
Plan amendments, settlements and curtailments	0	(4)
Foreign currency translation/other	(1)	0
Benefit obligation at end of year	88	74	83
Change in plan assets:
Beginning Balance	58	51
Employer contributions	4	4
Actual return on plan assets	3	6
Benefits paid	(3)	(3)
Plan amendments, settlements and curtailments	0	0
Foreign currency translation/other	(2)	0
Ending Balance	60	58	51
Funded (unfunded) status of the plans	(28)	(16)
International defined benefit pension plans
Change in benefit obligation:
Benefit obligation at beginning of year	703	707
Service cost	12	14	11
Interest cost	27	28	29
Benefits paid	(30)	(32)
Actuarial (gain) loss	144	(9)
Plan amendments, settlements and curtailments	(2)	(2)
Foreign currency translation/other	(70)	(3)
Benefit obligation at end of year	784	703	707
Change in plan assets:
Beginning Balance	466	426
Employer contributions	28	36
Actual return on plan assets	92	42
Benefits paid	(30)	(32)
Plan amendments, settlements and curtailments	(2)	(1)
Foreign currency translation/other	(30)	(5)
Ending Balance	524	466	426
Funded (unfunded) status of the plans	$ (260)	$ (237)