Accounts and Notes Receivable and Credit Quality of Receivables - Components of Notes Receivable, Net (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total accounts and notes receivable, net	$ 758	$ 753
Notes receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Notes receivable	160	178
Notes receivable allowance	(23)	(24)	$ (23)	$ (21)
Total accounts and notes receivable, net	137	154
Domestic | Notes receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Notes receivable	61	55
Notes receivable allowance	(6)	(6)
International | Notes receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Notes receivable	99	123
Notes receivable allowance	(17)	(18)
Balances over 90 days past due | Notes receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Notes receivable over 90 days past due	34	31
Notes receivable allowance for balances over 90 days past due	(23)	(24)
Notes receivable, net, balances over 90 days past due	11	7
Balances over 90 days past due | Domestic | Notes receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Notes receivable over 90 days past due	8	6
Notes receivable allowance for balances over 90 days past due	(6)	(6)
Balances over 90 days past due | International | Notes receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Notes receivable over 90 days past due	26	25
Notes receivable allowance for balances over 90 days past due	$ (17)	$ (18)