Restructuring Charges (Summary of Restructuring Plan) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Restructuring Cost and Reserve [Line Items]
Total restructuring charges	$ 0	$ 10
Asset impairment charges and accelerated depreciation expense
Restructuring Cost and Reserve [Line Items]
Total restructuring charges		1
Consulting services
Restructuring Cost and Reserve [Line Items]
Total restructuring charges		5
Other
Restructuring Cost and Reserve [Line Items]
Total restructuring charges		$ 4