v3.10.0.1
Fair Value of Financial Assets and Liabilities - Summary of Estimated Fair Value and Carrying Amount of Financial Instruments Measured on a Recurring Basis (Detail) - USD ($)
$ in Millions
Dec. 31, 2018
Dec. 31, 2017
Liabilities:    
Short-term debt $ (1,107) $ (751)
Long-term debt (6,247) (5,814)
Carrying Amount [Member] | Level III [Member]    
Assets:    
Notes hedges 24 301
Liabilities:    
Notes Embedded Conversion Derivative (24) (301)
Carrying Amount [Member] | Level II [Member]    
Assets:    
Other financial assets 32 29
Derivative instruments-assets 6 10
Liabilities:    
Short-term debt (2) (2)
Other long-term debt (25) (27)
Derivative instruments-liabilities (2) 0
Carrying Amount [Member] | Level II [Member] | Notes Payable to Banks [Member] | USD Notes [Member]    
Liabilities:    
Short-term debt 0 (749)
Long-term debt (6,222) (4,728)
Carrying Amount [Member] | Level II [Member] | Convertible Debt [Member] | 2019 Cash Convertible Senior Notes [Member]    
Liabilities:    
Short-term debt (1,105) (1,059)
Estimated Fair Value [Member] | Level III [Member]    
Assets:    
Notes hedges 24 301
Liabilities:    
Notes Embedded Conversion Derivative (24) (301)
Estimated Fair Value [Member] | Level II [Member]    
Assets:    
Other financial assets 32 29
Derivative instruments-assets 6 10
Liabilities:    
Short-term debt (2) (2)
Other long-term debt (25) (27)
Derivative instruments-liabilities (2) 0
Estimated Fair Value [Member] | Level II [Member] | Notes Payable to Banks [Member] | USD Notes [Member]    
Liabilities:    
Short-term debt 0 (755)
Long-term debt (6,191) (4,879)
Estimated Fair Value [Member] | Level II [Member] | Convertible Debt [Member] | 2019 Cash Convertible Senior Notes [Member]    
Liabilities:    
Short-term debt $ (1,327) $ (1,418)