Accounts Receivable and Notes Receivable and Credit Quality of Receivables - Components of Total Notes Receivable, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Receivables, net
Notes receivable	$ 25	$ 53
Notes receivable allowance for doubtful accounts		(42)	$ (40)
Accounts and notes receivable, net	636	808
Balances over 90 days past due
Stockholders' Equity Attributable to Parent	2,653	2,212
Cumulative Effect, Period of Adoption, Adjustment | Accumulated Loss
Balances over 90 days past due
Stockholders' Equity Attributable to Parent		6
Notes Receivable
Receivables, net
Notes receivable	722	844
Notes receivable allowance for doubtful accounts	(86)	(36)
Accounts and notes receivable, net	636	808
Balances over 90 days past due
Provision	(56)	(9)
Charge-offs and recoveries	12	13
Domestic
Receivables, net
Notes receivable allowance for doubtful accounts		(14)
Domestic | Notes Receivable
Receivables, net
Notes receivable	443	534
Notes receivable allowance for doubtful accounts	(43)	(13)
Balances over 90 days past due
Provision	(31)
Charge-offs and recoveries	2
International
Receivables, net
Notes receivable allowance for doubtful accounts		(28)
International | Notes Receivable
Receivables, net
Notes receivable	279	310
Notes receivable allowance for doubtful accounts	(43)	(23)
Balances over 90 days past due
Provision	(25)
Charge-offs and recoveries	10
Balances over 90 days past due | Notes Receivable
Balances over 90 days past due
Notes receivable, balances over 90 days past due	140	120
Notes receivable allowance for doubtful accounts, balances over 90 days past due	(50)	(31)
Notes receivable, net, balances over 90 days past due	90	89
Balances over 90 days past due | Domestic | Notes Receivable
Balances over 90 days past due
Notes receivable, balances over 90 days past due	88	65
Notes receivable allowance for doubtful accounts, balances over 90 days past due	(26)	(8)
Balances over 90 days past due | International | Notes Receivable
Balances over 90 days past due
Notes receivable, balances over 90 days past due	52	55
Notes receivable allowance for doubtful accounts, balances over 90 days past due	$ (24)	$ (23)