Segment Information (Reconciliation to Equipment Rentals Gross Profit) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Equipment rentals gross profit	$ 1,648	$ 1,585	$ 4,512	$ 4,251
Selling, general and administrative expenses	(416)	(374)	(1,209)	(1,134)
Restructuring charge	(1)	(5)	(3)	(24)
Non-rental depreciation and amortization	(109)	(107)	(322)	(329)
Interest expense, net	(178)	(163)	(511)	(474)
Other income, net	5	7	12	19
Income before provision for income taxes	949	943	2,479	2,309
Total equipment rentals gross profit
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Equipment rentals gross profit	1,442	1,350	3,830	3,526
Gross profit from other lines of business
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Equipment rentals gross profit	$ 206	$ 235	$ 682	$ 725

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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