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Revenue Recognition (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Contract with customer, liability	$ 104		$ 104		$ 83
Accounts receivable, net	1,744		1,744		1,677
Allowance for doubtful accounts	117		117		$ 112
Contract with customer, asset	0		0
Revenue recognized	0	$ 0	0	$ 0
Contract with customer, performance obligation satisfied in previous period	$ 0	$ 0	$ 0	$ 0
Revenues \| Largest customer \| Customer concentration risk
Property, Plant and Equipment [Line Items]
Concentration risk			1.00%
Accounts Receivable \| Largest customer \| Customer concentration risk
Property, Plant and Equipment [Line Items]
Concentration risk			1.00%		1.00%
Owned equipment rentals \| Revenues \| Product concentration risk
Property, Plant and Equipment [Line Items]
Concentration risk			72.00%
Equipment Rental \| Revenues \| Product concentration risk
Property, Plant and Equipment [Line Items]
Concentration risk			79.00%
US \| Revenues \| Geographic Concentration Risk
Property, Plant and Equipment [Line Items]
Concentration risk			90.00%
General rentals \| Revenues \| Product concentration risk
Property, Plant and Equipment [Line Items]
Concentration risk			74.00%