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Revenue Recognition (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Contract with customer, liability	$ 153		$ 153		$ 131
Accounts receivable, net	2,277		2,277		$ 2,004
Allowance for doubtful accounts	158		158
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%		1.00%	1.00%	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			70.00%
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			74.00%