Restructuring and Transformation Charges (Restructuring Charges) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges	$ 53	$ 27	$ 93	$ 90
2016-17 Plan [Member]
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges		27		90
2016-17 Plan [Member] | Western Hemisphere
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges		4		21
2016-17 Plan [Member] | Eastern Hemisphere
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges		5		32
2016-17 Plan [Member] | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges		18		37
2016-17 Plan [Member] | Employee Severance
Restructuring Cost and Reserve [Line Items]
Severance costs		6	10	46
2016-17 Plan [Member] | Employee Severance | Western Hemisphere
Restructuring Cost and Reserve [Line Items]
Severance costs		2		17
2016-17 Plan [Member] | Employee Severance | Eastern Hemisphere
Restructuring Cost and Reserve [Line Items]
Severance costs		2		20
2016-17 Plan [Member] | Employee Severance | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Severance costs		2		9
2016-17 Plan [Member] | Other Restructuring
Restructuring Cost and Reserve [Line Items]
Other restructuring costs		21	83	44
2016-17 Plan [Member] | Other Restructuring | Western Hemisphere
Restructuring Cost and Reserve [Line Items]
Other restructuring costs		2		4
2016-17 Plan [Member] | Other Restructuring | Eastern Hemisphere
Restructuring Cost and Reserve [Line Items]
Other restructuring costs		3		12
2016-17 Plan [Member] | Other Restructuring | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Other restructuring costs		$ 16		$ 28
Transformation Plan [Member]
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges	53		93
Transformation Plan [Member] | Western Hemisphere
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges	21		36
Transformation Plan [Member] | Eastern Hemisphere
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges	4		11
Transformation Plan [Member] | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges	28		46
Transformation Plan [Member] | Employee Severance
Restructuring Cost and Reserve [Line Items]
Severance costs	7		10
Transformation Plan [Member] | Employee Severance | Western Hemisphere
Restructuring Cost and Reserve [Line Items]
Severance costs	4		6
Transformation Plan [Member] | Employee Severance | Eastern Hemisphere
Restructuring Cost and Reserve [Line Items]
Severance costs	2		3
Transformation Plan [Member] | Employee Severance | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Severance costs	1		1
Transformation Plan [Member] | Other Restructuring
Restructuring Cost and Reserve [Line Items]
Other restructuring costs	46
Transformation Plan [Member] | Other Restructuring | Western Hemisphere
Restructuring Cost and Reserve [Line Items]
Other restructuring costs	17		30
Transformation Plan [Member] | Other Restructuring | Eastern Hemisphere
Restructuring Cost and Reserve [Line Items]
Other restructuring costs	2		8
Transformation Plan [Member] | Other Restructuring | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Other restructuring costs	$ 27		$ 45