Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Revenues:
Re-rent revenue, Topic 842	$ 34	$ 38
Ancillary and other rental revenues:
Revenues	2,125	2,117
Topic 842
Ancillary and other rental revenues:
Revenues	1,637	1,645
Topic 606
Ancillary and other rental revenues:
Revenues	488	472
Equipment rentals
Ancillary and other rental revenues:
Revenues	1,783	1,795
Equipment rentals \| Topic 842
Ancillary and other rental revenues:
Revenues	1,637	1,645
Equipment rentals \| Topic 606
Ancillary and other rental revenues:
Revenues	146	150
Owned equipment rentals
Revenues:
Owned equipment rentals, Topic 842	1,522
Owned equipment rentals, Topic 840		1,530
Owned equipment rentals \| Topic 842
Revenues:
Owned equipment rentals, Topic 842	1,522
Owned equipment rentals, Topic 840		1,530
Re-rent revenue
Revenues:
Re-rent revenue, Topic 842	34
Re-rent revenue, Topic 840		35
Re-rent revenue \| Topic 842
Revenues:
Re-rent revenue, Topic 842	34
Re-rent revenue, Topic 840		35
Ancillary and Other Rental Revenues
Revenues:
Revenue from contract with customer	119	119
Ancillary and other rental revenues:
Other	108	111
Revenues	227	230
Ancillary and Other Rental Revenues \| Topic 842
Revenues:
Revenue from contract with customer	0	0
Ancillary and other rental revenues:
Other	81	80
Revenues	81	80
Ancillary and Other Rental Revenues \| Topic 606
Revenues:
Revenue from contract with customer	119	119
Ancillary and other rental revenues:
Other	27	31
Revenues	146	150
Sales of rental equipment
Revenues:
Revenue from contract with customer	208	192
Sales of rental equipment \| Topic 606
Revenues:
Revenue from contract with customer	208	192
Sales of new equipment
Revenues:
Revenue from contract with customer	62	62
Sales of new equipment \| Topic 606
Revenues:
Revenue from contract with customer	62	62
Contractor supplies sales
Revenues:
Revenue from contract with customer	25	24
Contractor supplies sales \| Topic 606
Revenues:
Revenue from contract with customer	25	24
Service and other revenues
Revenues:
Revenue from contract with customer	47	44
Service and other revenues \| Topic 606
Revenues:
Revenue from contract with customer	$ 47	$ 44

Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919372-209981

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 45
-Paragraph 3
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 6A
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- Definition

The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The amount of revenue recognized for the period under subleasing arrangements.

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Amount of revenue and income classified as other.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
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