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Revenue Recognition (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Contract with customer, liability	$ 129		$ 131
Accounts receivable, net	2,034		$ 2,004
Allowance for doubtful accounts	146
Contract with customer, asset	0
Revenue recognized	0	$ 0
Contract with customer, performance obligation satisfied in previous period	$ 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	69.00%
Equipment Rental \| Revenues \| Product concentration risk
Property, Plant and Equipment [Line Items]
Concentration risk	76.00%
US \| Revenues \| Geographic Concentration Risk
Property, Plant and Equipment [Line Items]
Concentration risk	91.00%
General rentals \| Revenues \| Product concentration risk
Property, Plant and Equipment [Line Items]
Concentration risk	75.00%