Quarterly report pursuant to Section 13 or 15(d)

Long-Term Debt (Debt) (Details)

v3.7.0.1
Long-Term Debt (Debt) (Details) - USD ($)
$ in Millions
3 Months Ended 12 Months Ended
Mar. 31, 2017
Dec. 31, 2016
Debt Instrument [Line Items]    
Build to suit lease obligation $ 104 $ 105
Debt Issuance Costs (27) (28)
Total debt and capital lease obligations 5,103 5,289
Less current portion (15) (14)
Long-term portion of debt and capital lease obligations 5,088 5,275
3.125% Senior Secured Notes due 2019, net of original issue discount    
Debt Instrument [Line Items]    
Debt and Capital Lease Obligations $ 399 399
Debt instrument interest rate stated percentage 3.125%  
5.125% Senior Secured Notes due 2022    
Debt Instrument [Line Items]    
Debt and Capital Lease Obligations $ 500 500
Debt instrument interest rate stated percentage 5.125%  
4.375% Senior Secured Notes due 2023, net of original issue discount    
Debt Instrument [Line Items]    
Debt and Capital Lease Obligations $ 750 750
Debt instrument interest rate stated percentage 4.375%  
4.85% Senior Secured Notes due 2024, net of original issue discount    
Debt Instrument [Line Items]    
Debt and Capital Lease Obligations $ 600 600
Debt instrument interest rate stated percentage 4.85%  
4.45% Senior Secured Notes due 2025, net of original issue discount    
Debt Instrument [Line Items]    
Debt and Capital Lease Obligations $ 599 599
Debt instrument interest rate stated percentage 4.45%  
5.45% Senior Secured Notes due 2034, net of original issue discount    
Debt Instrument [Line Items]    
Debt and Capital Lease Obligations $ 399 399
Debt instrument interest rate stated percentage 5.45%  
5.95% Senior Secured Notes due 2043, net of original issue discount    
Debt Instrument [Line Items]    
Debt and Capital Lease Obligations $ 300 300
Debt instrument interest rate stated percentage 5.95%  
Senior secured credit facility    
Debt Instrument [Line Items]    
Debt and Capital Lease Obligations $ 1,404 1,596
Capital lease obligations    
Debt Instrument [Line Items]    
Debt and Capital Lease Obligations $ 75 $ 69