Goodwill and Other Intangible Assets (Goodwill) (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Goodwill [Roll Forward]
Beginning balance	$ 5,168
Goodwill related to acquisitions	670
Foreign currency translation and other adjustments	7
Ending balance	5,845
Goodwill accumulated impairment loss	1,557	$ 1,557
General rentals
Goodwill [Roll Forward]
Beginning balance	4,368
Goodwill related to acquisitions	118
Foreign currency translation and other adjustments	2
Ending balance	4,488
Specialty
Goodwill [Roll Forward]
Beginning balance	800
Goodwill related to acquisitions	552
Foreign currency translation and other adjustments	5
Ending balance	$ 1,357

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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