Fair Value of Financial Instruments - Carrying Values and Fair Values of Non-Current Financial Assets and Liabilities (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior, mezzanine, and other loans	$ 154	$ 117
Other noncurrent liabilities	(2,223)	(2,236)
Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior, mezzanine, and other loans	154	117
Total noncurrent financial assets	154	117
Senior Notes	(8,432)	(6,441)
Commercial paper / Credit Facility	(930)	(3,197)
Other long-term debt	(170)	(174)
Other noncurrent liabilities	(160)	(196)
Total noncurrent financial liabilities	(9,692)	(10,008)
Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior, mezzanine, and other loans	136	112
Total noncurrent financial assets	136	112
Senior Notes	(8,814)	(6,712)
Commercial paper / Credit Facility	(930)	(3,197)
Other long-term debt	(172)	(179)
Other noncurrent liabilities	(160)	(196)
Total noncurrent financial liabilities	$ (10,076)	$ (10,284)