Fair Value Measurements and Financial Instruments - Other Financial Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Other current assets
Schedule of Available for Sale Securities [Line Items]
Marketable securities	$ 14	$ 23
Assets
Schedule of Available for Sale Securities [Line Items]
Held-to-maturity securities	4	52
Bonds Issued By Argentinian Government | Other current assets
Schedule of Available for Sale Securities [Line Items]
Marketable securities	4
Fair Value, Inputs, Level 1 | Deposits | Other current assets
Schedule of Available for Sale Securities [Line Items]
Marketable securities	14
Fair Value, Inputs, Level 2 | Assets
Schedule of Available for Sale Securities [Line Items]
Held-to-maturity securities, fair value	$ 4	$ 64