Postretirement Benefit Plans - Amounts Recognized on our Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Overfunded retirement plans	$ 208	$ 96
Accrued expenses and other liabilities & Other long-term liabilities	(18)	(15)
Underfunded retirement plans	(89)	(129)
Funded status (FVPA – BO) at end of year	101	(48)
U.S. | Defined benefit plan
Defined Benefit Plan Disclosure [Line Items]
Overfunded retirement plans	58	66
Accrued expenses and other liabilities & Other long-term liabilities	(13)	(9)
Underfunded retirement plans	(48)	(53)
Funded status (FVPA – BO) at end of year	(3)	4
U.S. | Retiree health care plan
Defined Benefit Plan Disclosure [Line Items]
Overfunded retirement plans	0	3
Accrued expenses and other liabilities & Other long-term liabilities	0	0
Underfunded retirement plans	(20)	(3)
Funded status (FVPA – BO) at end of year	(20)	0
Non-U.S. | Defined benefit plan
Defined Benefit Plan Disclosure [Line Items]
Overfunded retirement plans	150	27
Accrued expenses and other liabilities & Other long-term liabilities	(5)	(6)
Underfunded retirement plans	(21)	(73)
Funded status (FVPA – BO) at end of year	$ 124	$ (52)