Segment Information (Reconciliation to Income (loss) from Continuing Operations) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Equipment rentals gross profit	$ 727	$ 761
Selling, general and administrative expenses	(267)	(280)
Merger related costs	0	(1)
Restructuring charge	(2)	(8)
Non-rental depreciation and amortization	(100)	(104)
Interest expense, net	(136)	(151)
Other income, net	4	3
Income before provision for income taxes	226	220
Equipment rentals under operating lease
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Equipment rentals gross profit	610	658
Other lines of business
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Equipment rentals gross profit	$ 117	$ 103

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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