Segment Information (Reconciliation to Income (loss) from Continuing Operations) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Equipment rentals gross profit	$ 701	$ 911	$ 1,428	$ 1,672
Selling, general and administrative expenses	(222)	(271)	(489)	(551)
Merger related costs	0	0	0	(1)
Restructuring charge	(3)	(6)	(5)	(14)
Non-rental depreciation and amortization	(95)	(105)	(195)	(209)
Interest expense, net	(130)	(180)	(266)	(331)
Other income, net	0	2	4	5
Income before provision for income taxes	251	351	477	571
Equipment rentals under operating lease
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Equipment rentals gross profit	600	792	1,210	1,450
Other lines of business
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Equipment rentals gross profit	$ 101	$ 119	$ 218	$ 222

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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