Revenue Recognition Accounting Policy (Details 3) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Revenues		$ 1,198	$ 1,310	$ 2,461	$ 2,564
Deferred Revenue		$ 420		420		$ 441
Deferred Revenue, Revenue Recognized				(37)
Deferred Revenue, Additions				24
Foreign Currency Gain (Loss) and Refranchising Gain (Loss) [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Deferred Revenue, Period Increase (Decrease)	[1]			$ (8)

[1] (a) Primarily includes impact of foreign currency translation.