Schedule of Goodwill (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Goodwill [Line Items]
Gross goodwill			$ 2,493us-gaap_GoodwillGross
Goodwill [Roll Forward]
Goodwill	691us-gaap_Goodwill	375us-gaap_Goodwill
Goodwill, Impaired, Accumulated Impairment Loss			(2,118)
Acquisition	203us-gaap_GoodwillAcquiredDuringPeriod	300us-gaap_GoodwillAcquiredDuringPeriod
Adjustments to the allocation of purchase price	(52)	16
Goodwill	842us-gaap_Goodwill	691us-gaap_Goodwill
North America
Goodwill [Line Items]
Gross goodwill			1,360
Goodwill [Roll Forward]
Goodwill	301	5
Goodwill, Impaired, Accumulated Impairment Loss			(1,355)
Acquisition	190	296
Adjustments to the allocation of purchase price	(28)	0
Goodwill	463	301
International
Goodwill [Line Items]
Gross goodwill			890
Goodwill [Roll Forward]
Goodwill	375	355
Goodwill, Impaired, Accumulated Impairment Loss			(535)
Acquisition	13	4
Adjustments to the allocation of purchase price	(24)	16
Goodwill	364	375
Truck Rental
Goodwill [Line Items]
Gross goodwill			243
Goodwill [Roll Forward]
Goodwill	15	15
Goodwill, Impaired, Accumulated Impairment Loss			(228)
Acquisition	0	0
Adjustments to the allocation of purchase price	0	0
Goodwill	$ 15	$ 15

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

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments 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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