Restructuring Charges - (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Restructuring Reserve [Roll Forward]
December 31, 2016			$ 87
Charge to Earnings	$ 59	$ 40	105	$ 87
Cash Paid			(71)
Non-cash and Other			(14)
June 30, 2017	107		107
Employee termination costs
Restructuring Reserve [Roll Forward]
December 31, 2016			71
Charge to Earnings			61
Cash Paid			(54)
Non-cash and Other			6
June 30, 2017	84		84
Asset impairment costs
Restructuring Reserve [Roll Forward]
December 31, 2016			0
Charge to Earnings			20
Cash Paid			0
Non-cash and Other			(20)
June 30, 2017	0		0
Facility exit costs
Restructuring Reserve [Roll Forward]
December 31, 2016			2
Charge to Earnings			13
Cash Paid			(10)
Non-cash and Other			0
June 30, 2017	5		5
Other exit costs
Restructuring Reserve [Roll Forward]
December 31, 2016			14
Charge to Earnings			11
Cash Paid			(7)
Non-cash and Other			0
June 30, 2017	$ 18		$ 18