Financial Instruments and Risk Management - Fair Value (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Fair Value Measurements
Total current derivative contracts, assets	$ 213	$ 82
Total noncurrent derivative contracts, assets	58	8
Total current derivative contracts, liabilities	59	84
Total noncurrent derivative contracts, liabilities	3	10
Commodity contracts
Fair Value Measurements
Total current derivative contracts, assets	188	50
Total noncurrent derivative contracts, assets	11
Total current derivative contracts, liabilities	45	17
Total noncurrent derivative contracts, liabilities		10
Currency contracts
Fair Value Measurements
Total current derivative contracts, assets	23	30
Total noncurrent derivative contracts, assets	47	8
Total current derivative contracts, liabilities	5	63
Total noncurrent derivative contracts, liabilities	3
Cross-currency and other contracts
Fair Value Measurements
Total current derivative contracts, assets	2	2
Total current derivative contracts, liabilities	9	4
Derivatives Designated As Hedging Instruments
Fair Value Measurements
Total current derivative contracts, assets	192	53
Total noncurrent derivative contracts, assets	58	8
Total current derivative contracts, liabilities	45	17
Total noncurrent derivative contracts, liabilities		8
Derivatives Designated As Hedging Instruments | Commodity contracts
Fair Value Measurements
Total current derivative contracts, assets	188	50
Total noncurrent derivative contracts, assets	11
Total current derivative contracts, liabilities	45	17
Total noncurrent derivative contracts, liabilities		8
Derivatives Designated As Hedging Instruments | Currency contracts
Fair Value Measurements
Total current derivative contracts, assets	4	3
Total noncurrent derivative contracts, assets	47	8
Derivatives Not Designated as Hedging Instruments
Fair Value Measurements
Total current derivative contracts, assets	21	29
Total current derivative contracts, liabilities	14	67
Total noncurrent derivative contracts, liabilities	3	2
Derivatives Not Designated as Hedging Instruments | Commodity contracts
Fair Value Measurements
Total noncurrent derivative contracts, liabilities		2
Derivatives Not Designated as Hedging Instruments | Currency contracts
Fair Value Measurements
Total current derivative contracts, assets	19	27
Total current derivative contracts, liabilities	5	63
Total noncurrent derivative contracts, liabilities	3
Derivatives Not Designated as Hedging Instruments | Cross-currency and other contracts
Fair Value Measurements
Total current derivative contracts, assets	2	2
Total current derivative contracts, liabilities	$ 9	$ 4