Restructuring (Summary Of Changes To Restructuring-Related Liabilities) (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restructuring Reserve [Roll Forward]
Balance as of January 1, 2020			$ 6
Restructuring expense	$ (17)	$ (22)	(89)	$ (66)
Balance as of September 30, 2020	10		10
Americas
Restructuring Reserve [Roll Forward]
Balance as of January 1, 2020			2
Balance as of September 30, 2020	2		2
International [Member]
Restructuring Reserve [Roll Forward]
Balance as of January 1, 2020			4
Balance as of September 30, 2020	8		8
2020 Optimization [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			(59)
Payment for Restructuring			(50)
2020 Optimization [Member] | Americas
Restructuring Reserve [Roll Forward]
Restructuring expense			(26)
Payment for Restructuring			(24)
2020 Optimization [Member] | International [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			(33)
Payment for Restructuring			(26)
Brazil Restructuring [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			(2)
Payment for Restructuring			(2)
Brazil Restructuring [Member] | Americas
Restructuring Reserve [Roll Forward]
Restructuring expense			(2)
Payment for Restructuring			(2)
Brazil Restructuring [Member] | International [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			0
Payment for Restructuring			0
T19 Restructuring [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			(4)
Payment for Restructuring			(9)
T19 Restructuring [Member] | Americas
Restructuring Reserve [Roll Forward]
Restructuring expense			(4)
Payment for Restructuring			(6)
T19 Restructuring [Member] | International [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			0
Payment for Restructuring			(3)
Personnel
Restructuring Reserve [Roll Forward]
Balance as of January 1, 2020			3
Balance as of September 30, 2020	6		6
Personnel | 2020 Optimization [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			(56)
Payment for Restructuring			(49)
Personnel | Brazil Restructuring [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			(1)
Payment for Restructuring			(1)
Personnel | T19 Restructuring [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			0
Payment for Restructuring			(4)
Facility Closing [Member]
Restructuring Reserve [Roll Forward]
Balance as of January 1, 2020			1
Balance as of September 30, 2020	2		2
Facility Closing [Member] | 2020 Optimization [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			(1)
Payment for Restructuring			0
Facility Closing [Member] | Brazil Restructuring [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			(1)
Payment for Restructuring			(1)
Facility Closing [Member] | T19 Restructuring [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			0
Payment for Restructuring			0
Other Restructuring [Member]
Restructuring Reserve [Roll Forward]
Balance as of January 1, 2020			2
Balance as of September 30, 2020	$ 2		2
Other Restructuring [Member] | 2020 Optimization [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			(2)
Payment for Restructuring			(1)
Other Restructuring [Member] | Brazil Restructuring [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			0
Payment for Restructuring			0
Other Restructuring [Member] | T19 Restructuring [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense			(4)
Payment for Restructuring			$ (5)