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Basis of Presentation - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts and notes receivable, net, allowance for credit losses	$ 178	$ 101	$ 82
Deferred tax liabilities	212		290
Stockholder's equity	(20)		703	$ 1,603	$ 2,225
Change in allowance for credit losses from COVID-19	78
Adoption of ASU 2016-13 \| Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts and notes receivable, net, allowance for credit losses		19
Deferred tax liabilities		(4)
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholder's equity	$ 9,504		$ 9,644	$ 9,219	$ 8,982
Retained Earnings \| Adoption of ASU 2016-13 \| Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholder's equity		$ (15)