Fair Value Measurements - Fair Value Associated With Derivative Financial Instruments (Details) - Level 2 - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Derivative Assets
Gross Fair Value	$ 14	$ 116
Impact of Netting	(5)	(2)
Derivative Liabilities
Gross Fair Value	(5)	(2)
Impact of Netting	5	2
Current Assets
Derivative Assets
Derivatives instruments	9	101
Non-current Assets
Derivative Assets
Derivatives instruments	0	13
Current Liabilities
Derivative Liabilities
Derivatives instruments	0	0
Non-current Liabilities
Derivative Liabilities
Derivatives instruments	$ 0	$ 0

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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