Restructuring, Facility Consolidation and Severance Charges (Restructuring Charges) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges	$ 31	$ 53	$ 114	$ 93
Restructuring Charges
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges	31	53	114	93
Restructuring Charges | Western Hemisphere
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges	17	21	58	36
Restructuring Charges | Eastern Hemisphere
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges	12	4	29	11
Restructuring Charges | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Severance, asset impairment and other restructuring charges	2	28	27	46
Restructuring Charges | Employee Severance
Restructuring Cost and Reserve [Line Items]
Severance costs	31	7	109	10
Restructuring Charges | Facility Consolidation and Other Charges
Restructuring Cost and Reserve [Line Items]
Other restructuring costs	0	40	5	69
Restructuring Charges | Asset Related Charges
Restructuring Cost and Reserve [Line Items]
Other restructuring costs	$ 0	$ 6	$ 0	$ 14