Geographic and Customer Concentrations - Revenue from Geographical Region (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Total operating revenue	$ 7,952	$ 7,933	$ 7,773
North America
Disaggregation of Revenue [Line Items]
Total operating revenue	6,365	6,411	6,307
Europe, Middle East and Africa
Disaggregation of Revenue [Line Items]
Total operating revenue	805	785	719
Latin America
Disaggregation of Revenue [Line Items]
Total operating revenue	$ 782	$ 737	$ 747