Restructuring - Summary of Utilization of Restructuring Accruals (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Utilization of restructuring accruals [Roll Forward]
Restructuring, net	$ 24	$ 19	$ 45	$ 20
Employee Severance
Utilization of restructuring accruals [Roll Forward]
Remaining accrual at the beginning of the period			29
Restructuring, net			24
Impairment of held-for-sale assets			0
Cash payments and other			(36)
Remaining accrual at the end of the period	17		17
Other
Utilization of restructuring accruals [Roll Forward]
Remaining accrual at the beginning of the period			1
Restructuring, net			21
Impairment of held-for-sale assets			(21)
Cash payments and other			0
Remaining accrual at the end of the period	$ 1		$ 1