v3.6.0.2
Debt - Schedule of Long-Term Debt (Detail) - USD ($)
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Debt Instrument [Line Items]    
Average rate of interest 3.70%  
Principal amount outstanding $ 9,361,000,000 $ 9,343,000,000
Due in 2017 421,000,000  
Due after 2017 8,955,000,000  
Due after 2021 $ 2,800,000,000  
Average remaining term (in years) 4 years 1 month 6 days  
Revolving Credit Facility [Member]    
Debt Instrument [Line Items]    
Range of interest rates [1] 0.00%  
Average rate of interest [1] 0.00%  
Principal amount outstanding [1] $ 0 0
Due in 2017 [1] 0  
Due after 2017 [1] 0  
Due after 2021 [1] $ 0  
Average remaining term (in years) [1] 0 years  
Notes Payable to Banks [Member] | USD Notes [Member]    
Debt Instrument [Line Items]    
Average rate of interest 4.10%  
Principal amount outstanding $ 8,211,000,000 8,193,000,000
Due in 2017 406,000,000  
Due after 2017 7,805,000,000  
Due after 2021 $ 2,800,000,000  
Average remaining term (in years) 4 years 2 months 12 days  
Notes Payable to Banks [Member] | USD Notes [Member] | Minimum [Member]    
Debt Instrument [Line Items]    
Range of interest rates 2.80%  
Notes Payable to Banks [Member] | USD Notes [Member] | Maximum [Member]    
Debt Instrument [Line Items]    
Range of interest rates 5.80%  
Convertible Debt [Member] | 2019 Cash Convertible Senior Notes [Member]    
Debt Instrument [Line Items]    
Average rate of interest 1.00%  
Principal amount outstanding $ 1,150,000,000 1,150,000,000
Due in 2017 0  
Due after 2017 1,150,000,000  
Due after 2021 $ 0  
Average remaining term (in years) 2 years 10 months 24 days  
Convertible Debt [Member] | 2019 Cash Convertible Senior Notes [Member] | Minimum [Member]    
Debt Instrument [Line Items]    
Range of interest rates 1.00%  
Convertible Debt [Member] | 2019 Cash Convertible Senior Notes [Member] | Maximum [Member]    
Debt Instrument [Line Items]    
Range of interest rates 1.00%  
Bank Borrowings [Member]    
Debt Instrument [Line Items]    
Range of interest rates 0.00%  
Average rate of interest 0.00%  
Principal amount outstanding $ 0 0
Due in 2017 0  
Due after 2017 0  
Due after 2021 $ 0  
Average remaining term (in years) 0 years  
Capital Lease [Member]    
Debt Instrument [Line Items]    
Average rate of interest 3.00%  
Principal amount outstanding $ 15,000,000 $ 31,000,000
Due in 2017 15,000,000  
Due after 2017 0  
Due after 2021 $ 0  
Average remaining term (in years) 1 year 3 months 18 days  
Capital Lease [Member] | Minimum [Member]    
Debt Instrument [Line Items]    
Range of interest rates 2.50%  
Capital Lease [Member] | Maximum [Member]    
Debt Instrument [Line Items]    
Range of interest rates 13.80%  
[1] We do not have any borrowings under the $600 million Revolving Credit Facility as of December 31, 2016.