Schedule of Goodwill (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Goodwill [Line Items]
Gross goodwill			$ 2,471
Accumulated impairment losses			(2,118)
Goodwill [Roll Forward]
Goodwill	375	353
Acquisition	300	17
Adjustments to the allocation of purchase price		5
Foreign currency translation adjustments	16
Goodwill	691	375
North America
Goodwill [Line Items]
Gross goodwill			1,359
Accumulated impairment losses			(1,355)
Goodwill [Roll Forward]
Goodwill	5	4
Acquisition	296	1
Adjustments to the allocation of purchase price		0
Foreign currency translation adjustments	0
Goodwill	301	5
International
Goodwill [Line Items]
Gross goodwill			869
Accumulated impairment losses			(535)
Goodwill [Roll Forward]
Goodwill	355	334
Acquisition	4	16
Adjustments to the allocation of purchase price		5
Foreign currency translation adjustments	16
Goodwill	375	355
Truck Rental
Goodwill [Line Items]
Gross goodwill			243
Accumulated impairment losses			(228)
Goodwill [Roll Forward]
Goodwill	15	15
Acquisition	0	0
Adjustments to the allocation of purchase price		0
Foreign currency translation adjustments	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

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=14024403&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

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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 increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e961-128460

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