Pension, Other Postretirement Benefits and Savings Plans - Changes in Benefit Obligation and Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Change in benefit obligation:
Curtailments/settlements	$ 139	$ 39	$ 0
U.S.
Change in benefit obligation:
Beginning balance	(6,507)	(5,981)
Newly adopted plans	0	0
Service cost — benefits earned	(4)	(15)	(45)
Interest cost	(238)	(256)	(243)
Plan amendments	0	1
Actuarial gain (loss)	262	(693)
Participant contributions	0	0
Curtailments/settlements	285	1
Divestitures	500	0
Deconsolidation of Venezuelan subsidiary	0	0
Foreign currency translation	0	0
Benefit payments	364	436
Ending balance	(5,338)	(6,507)	(5,981)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	6,250	4,800
Newly adopted plans	0	0
Actual return on plan assets	(117)	711
Company contributions to plan assets	0	1,167
Cash funding of direct participant payments	7	9
Participant contributions	0	0
Settlements	(285)	(1)
Divestitures	(480)	0
Foreign currency translation	0	0
Benefit payments	(364)	(436)
Ending balance	5,011	6,250	4,800
Funded status at end of year	(327)	(257)
Non-U.S.
Change in benefit obligation:
Beginning balance	(3,178)	(3,129)
Newly adopted plans	(9)	(3)
Service cost — benefits earned	(43)	(34)	(39)
Interest cost	(113)	(131)	(131)
Plan amendments	0	(2)
Actuarial gain (loss)	(5)	(394)
Participant contributions	(2)	(2)
Curtailments/settlements	19	69
Divestitures	0	0
Deconsolidation of Venezuelan subsidiary	80	0
Foreign currency translation	303	284
Benefit payments	140	164
Ending balance	(2,808)	(3,178)	(3,129)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	2,721	2,455
Newly adopted plans	9	0
Actual return on plan assets	60	505
Company contributions to plan assets	60	118
Cash funding of direct participant payments	36	44
Participant contributions	2	2
Settlements	(18)	(39)
Divestitures	0	0
Foreign currency translation	(237)	(200)
Benefit payments	(140)	(164)
Ending balance	2,493	2,721	2,455
Funded status at end of year	(315)	(457)
Other Postretirement Benefits
Change in benefit obligation:
Beginning balance	(361)	(388)
Newly adopted plans	0	0
Service cost — benefits earned	(3)	(4)	(6)
Interest cost	(15)	(19)	(19)
Plan amendments	0	0
Actuarial gain (loss)	22	0
Participant contributions	(15)	(16)
Curtailments/settlements	0	0
Divestitures	6	0
Deconsolidation of Venezuelan subsidiary	0	0
Foreign currency translation	35	17
Benefit payments	40	49
Ending balance	(291)	(361)	(388)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	5	5
Newly adopted plans	0	0
Actual return on plan assets	0	0
Company contributions to plan assets	2	2
Cash funding of direct participant payments	23	31
Participant contributions	15	16
Settlements	0	0
Divestitures	0	0
Foreign currency translation	(2)	0
Benefit payments	(40)	(49)
Ending balance	3	5	$ 5
Funded status at end of year	$ (288)	$ (356)