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Restructuring Charges and Asset Impairments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		$ 116
Asset Impairments		98
Total Restructuring Charges & Asset Impairments	$ 2	214	$ 0
Government Solutions
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		2
Asset Impairments		2
Total Restructuring Charges & Asset Impairments		4
Sustainable Technology Solutions
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		39
Asset Impairments		47
Total Restructuring Charges & Asset Impairments		86
Other
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		75
Asset Impairments		49
Total Restructuring Charges & Asset Impairments		124
Severance
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		32
Severance \| Government Solutions
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		2
Severance \| Sustainable Technology Solutions
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		29
Severance \| Other
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		1
Lease Abandonment
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		58
Lease Abandonment \| Government Solutions
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		0
Lease Abandonment \| Sustainable Technology Solutions
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		4
Lease Abandonment \| Other
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		54
Other
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		26
Other \| Government Solutions
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		0
Other \| Sustainable Technology Solutions
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		6
Other \| Other
Restructuring Cost and Reserve [Line Items]
Total Restructuring Charges		$ 20