Fair Value Measurements and Financial Instruments - Fair Value of Derivative Instruments and Other Financial Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Designated derivative instruments
Derivative assets, designated	$ 13	$ 20
Derivative liabilities, designated	30	38
Other financial instruments
Total other financial instruments	66	10
Other current assets
Other financial instruments
Marketable securities	66	10
Other current assets | Interest rate swap contracts
Designated derivative instruments
Derivative assets, designated	0	0
Other current assets | Foreign currency contracts
Designated derivative instruments
Derivative assets, designated	9	20
Other current assets | Commodity contracts
Designated derivative instruments
Derivative assets, designated	0	0
Other assets | Interest rate swap contracts
Designated derivative instruments
Derivative assets, designated	4	0
Other assets | Foreign currency contracts
Designated derivative instruments
Derivative assets, designated	0	0
Other accruals | Interest rate swap contracts
Designated derivative instruments
Derivative liabilities, designated	0	1
Other accruals | Foreign currency contracts
Designated derivative instruments
Derivative liabilities, designated	11	8
Other accruals | Commodity contracts
Designated derivative instruments
Derivative liabilities, designated	0	0
Other liabilities | Interest rate swap contracts
Designated derivative instruments
Derivative liabilities, designated	0	8
Other liabilities | Foreign currency contracts
Designated derivative instruments
Derivative liabilities, designated	$ 19	$ 21