Defined Benefit Postretirement Plans (Details) - USD ($) $ in Millions		3 Months Ended				6 Months Ended
		Jun. 30, 2016		Jun. 30, 2015		Dec. 31, 2016	Jun. 30, 2016		Jun. 30, 2015
Pension and Other Postretirement Benefit Contributions [Abstract]
Pension Contributions							$ 30
Defined Benefit Plan, Benefits Paid							37
Other Postretirement Benefits Payments							10
Scenario, Forecast [Member]
Pension and Other Postretirement Benefit Contributions [Abstract]
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year						$ 34
United States and Foreign Pension Plans Defined Benefit [Member]
Defined Benefit Plan Net Periodic Benefit Cost [Line Items]
Service cost		$ 6		$ 12			12		$ 24
Interest cost		10		13			21		27
Expected return on plan assets		(13)		(17)			(28)		(36)
Amortization:
- prior service cost (credit)		(3)		(2)			(5)		(1)
-actuarial loss (gain)		4		7			7		14
Net settlement loss		31		64			79		81	[1]
Defined Benefit Plan, Curtailments	[2]	0		0			0		1
Net periodic benefit cost		35		77			86		110
Other Postretirement Benefit Plans Defined Benefit [Member]
Defined Benefit Plan Net Periodic Benefit Cost [Line Items]
Service cost		1		1			2		2
Interest cost		2		2			5		5
Expected return on plan assets		0		0			0		0
Amortization:
- prior service cost (credit)		(1)		(1)			(2)		(2)
-actuarial loss (gain)		0		0			0		0
Net settlement loss	[1]	0		0			0		0
Defined Benefit Plan, Curtailments		0	[2]	2	[2]		0	[2]	(4)
Net periodic benefit cost		$ 2		$ 4			$ 5		$ 1

[1] Settlements are recognized as they occur, once it is probable that lump sum payments from a plan for a given year will exceed the plan's total service and interest cost for that year.

[2] Related to workforce reductions, which reduced the future expected years of service for employees participating in the plans