Goodwill and Other Intangible Assets (Goodwill) (Details) $ in Millions	9 Months Ended
Sep. 30, 2018 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 4,082
Goodwill related to acquisitions	238
Foreign currency translation and other adjustments	(7)
Ending balance	4,313
General rentals
Goodwill [Roll Forward]
Beginning balance	3,607
Goodwill related to acquisitions	44
Foreign currency translation and other adjustments	(6)
Ending balance	3,645
Goodwill accumulated impairment loss	1,557
Trench, power and fluid solutions
Goodwill [Roll Forward]
Beginning balance	475
Goodwill related to acquisitions	194
Foreign currency translation and other adjustments	(1)
Ending balance	$ 668

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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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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