Financial Instruments, Derivatives and Hedging Activities - Balance Sheet Location (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Designated as Hedging Instrument
Fair value of derivatives
Fair value of derivative instruments, Assets	$ 6	$ 17
Fair value of derivative instruments, Liabilities	30	25
Fair value of derivative instruments, Net Assets/(Liabilities)	(24)	(8)
Designated as Hedging Instrument | Accounts receivable, net
Fair value of derivatives
Fair value of derivative instruments, Assets	3	12
Designated as Hedging Instrument | Other assets
Fair value of derivatives
Fair value of derivative instruments, Assets	3	5
Designated as Hedging Instrument | Accounts payable and accrued liabilities
Fair value of derivatives
Fair value of derivative instruments, Liabilities	28	17
Designated as Hedging Instrument | Non-current liabilities
Fair value of derivatives
Fair value of derivative instruments, Liabilities	2	8
Designated as Hedging Instrument | Commodity Contracts
Fair value of derivatives
Fair value of derivative instruments, Assets	5	6
Fair value of derivative instruments, Liabilities	28	17
Fair value of derivative instruments, Net Assets/(Liabilities)	(23)	(11)
Designated as Hedging Instrument | Commodity Contracts | Accounts receivable, net
Fair value of derivatives
Fair value of derivative instruments, Assets	3	5
Designated as Hedging Instrument | Commodity Contracts | Other assets
Fair value of derivatives
Fair value of derivative instruments, Assets	2	1
Designated as Hedging Instrument | Commodity Contracts | Accounts payable and accrued liabilities
Fair value of derivatives
Fair value of derivative instruments, Liabilities	26	13
Designated as Hedging Instrument | Commodity Contracts | Non-current liabilities
Fair value of derivatives
Fair value of derivative instruments, Liabilities	2	4
Designated as Hedging Instrument | Foreign Currency Forward Contracts
Fair value of derivatives
Fair value of derivative instruments, Assets	1	10
Fair value of derivative instruments, Liabilities	2	8
Fair value of derivative instruments, Net Assets/(Liabilities)	(1)	2
Designated as Hedging Instrument | Foreign Currency Forward Contracts | Accounts receivable, net
Fair value of derivatives
Fair value of derivative instruments, Assets		7
Designated as Hedging Instrument | Foreign Currency Forward Contracts | Other assets
Fair value of derivatives
Fair value of derivative instruments, Assets	1	3
Designated as Hedging Instrument | Foreign Currency Forward Contracts | Accounts payable and accrued liabilities
Fair value of derivatives
Fair value of derivative instruments, Liabilities	2	4
Designated as Hedging Instrument | Foreign Currency Forward Contracts | Non-current liabilities
Fair value of derivatives
Fair value of derivative instruments, Liabilities		4
Designated as Hedging Instrument | Interest Rate Contracts
Fair value of derivatives
Fair value of derivative instruments, Assets		1
Fair value of derivative instruments, Net Assets/(Liabilities)		1
Designated as Hedging Instrument | Interest Rate Contracts | Other assets
Fair value of derivatives
Fair value of derivative instruments, Assets		1
Not Designated as Hedging Instrument
Fair value of derivatives
Fair value of derivative instruments, Assets	6	7
Fair value of derivative instruments, Liabilities	23	11
Fair value of derivative instruments, Net Assets/(Liabilities)	(17)	(4)
Not Designated as Hedging Instrument | Accounts receivable, net
Fair value of derivatives
Fair value of derivative instruments, Assets	5	6
Not Designated as Hedging Instrument | Other assets
Fair value of derivatives
Fair value of derivative instruments, Assets	1	1
Not Designated as Hedging Instrument | Accounts payable and accrued liabilities
Fair value of derivatives
Fair value of derivative instruments, Liabilities	20	9
Not Designated as Hedging Instrument | Non-current liabilities
Fair value of derivatives
Fair value of derivative instruments, Liabilities	3	2
Not Designated as Hedging Instrument | Commodity Contracts
Fair value of derivatives
Fair value of derivative instruments, Assets		2
Fair value of derivative instruments, Liabilities	4	1
Fair value of derivative instruments, Net Assets/(Liabilities)	(4)	1
Not Designated as Hedging Instrument | Commodity Contracts | Accounts receivable, net
Fair value of derivatives
Fair value of derivative instruments, Assets		2
Not Designated as Hedging Instrument | Commodity Contracts | Accounts payable and accrued liabilities
Fair value of derivatives
Fair value of derivative instruments, Liabilities	4	1
Not Designated as Hedging Instrument | Foreign Currency Forward Contracts
Fair value of derivatives
Fair value of derivative instruments, Assets	6	5
Fair value of derivative instruments, Liabilities	19	10
Fair value of derivative instruments, Net Assets/(Liabilities)	(13)	(5)
Not Designated as Hedging Instrument | Foreign Currency Forward Contracts | Accounts receivable, net
Fair value of derivatives
Fair value of derivative instruments, Assets	5	4
Not Designated as Hedging Instrument | Foreign Currency Forward Contracts | Other assets
Fair value of derivatives
Fair value of derivative instruments, Assets	1	1
Not Designated as Hedging Instrument | Foreign Currency Forward Contracts | Accounts payable and accrued liabilities
Fair value of derivatives
Fair value of derivative instruments, Liabilities	16	8
Not Designated as Hedging Instrument | Foreign Currency Forward Contracts | Non-current liabilities
Fair value of derivatives
Fair value of derivative instruments, Liabilities	$ 3	$ 2