Commitments and Contingencies - Future Minimum Commitments Under Our corporate Headquarters Lease and Other Non-Cancelable Operating Leases (Parenthetical) (Details) - USD ($) $ in Millions		Dec. 31, 2015	Dec. 31, 2014
Commitments And Contingencies Disclosure [Abstract]
Other long-term liabilities under financial obligation	[1]	$ 84	$ 67

[1] Refer to “Note 12 – Commitments and Contingencies,” for additional information on our corporate headquarters lease.