Segment Information (Reconciliation to Income (loss) from Continuing Operations) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Equipment rentals gross profit	$ 875	$ 701	$ 1,589	$ 1,428
Selling, general and administrative expenses	(301)	(222)	(551)	(489)
Merger related costs	(3)	0	(3)	0
Restructuring charge	0	(3)	(1)	(5)
Non-rental depreciation and amortization	(90)	(95)	(181)	(195)
Interest expense, net	(100)	(130)	(199)	(266)
Other (expense) income, net	(4)	0	(2)	4
Income before provision for income taxes	377	251	652	477
Total equipment rentals gross profit
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Equipment rentals gross profit	751	600	1,328	1,210
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	$ 124	$ 101	$ 261	$ 218