Segment Information (Narrative) (Detail) (USD $)	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012		Dec. 31, 2012
Segment Reporting Information [Line Items]
Sales Revenue, Services, Net	$ 2,395,000,000		$ 2,170,000,000		$ 6,087,000,000		$ 5,659,000,000
Adjusted EBITDA	369,000,000	[1]	370,000,000	[1]	615,000,000	[2]	736,000,000	[2]
Non Vehicle Related Depreciation And Amortization	39,000,000		30,000,000		109,000,000		92,000,000
Interest expense	57,000,000		67,000,000		170,000,000		208,000,000
Early Debt Extinguishment	0		2,000,000		131,000,000		52,000,000
Transaction-related costs	10,000,000	[3]	11,000,000	[3]	37,000,000	[4]	21,000,000	[4]
Restructuring expense	14,000,000		7,000,000		39,000,000		26,000,000
Assets under vehicle programs	11,883,000,000				11,883,000,000				10,099,000,000
Non current deferred tax assets	1,351,000,000				1,351,000,000				1,454,000,000
Loss before income taxes	230,000,000		260,000,000		135,000,000		363,000,000
Other than Temporary Impairment Losses, Investments	33,000,000		0		33,000,000		0
North America [Member]
Segment Reporting Information [Line Items]
Sales Revenue, Services, Net	1,513,000,000		1,358,000,000		3,905,000,000		3,580,000,000
Adjusted EBITDA	223,000,000		232,000,000		427,000,000		509,000,000
Restructuring expense					6,000,000
Assets under vehicle programs	8,700,000,000		7,400,000,000		8,700,000,000		7,400,000,000
Segment Assets Exclusive Of Assets Under Vehicle Program	3,700,000,000		3,100,000,000		3,700,000,000		3,100,000,000
International [Member]
Segment Reporting Information [Line Items]
Sales Revenue, Services, Net	773,000,000		703,000,000		1,895,000,000		1,791,000,000
Adjusted EBITDA	144,000,000		129,000,000		211,000,000		210,000,000
Restructuring expense					14,000,000
Truck Rental [Member]
Segment Reporting Information [Line Items]
Sales Revenue, Services, Net	109,000,000		109,000,000		287,000,000		287,000,000
Adjusted EBITDA	13,000,000		14,000,000		12,000,000		32,000,000
Restructuring expense					19,000,000
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Sales Revenue, Services, Net	0	[5]	0	[5]	0	[5]	1,000,000	[5]
Adjusted EBITDA	$ (11,000,000)	[5]	$ (5,000,000)	[5]	$ (35,000,000)	[5]	$ (15,000,000)	[5]

[1] Adjusted EBITDA for the three months ended September 30, 2013 and 2012, includes $14 million and $7 million, respectively, of restructuring expense.

[2] Adjusted EBITDA for the nine months ended September 30, 2013 and 2012, includes $39 million and $26 million, respectively, of restructuring expense.

[3] During the three months ended September 30, 2013, the Company incurred $10 million in transaction-related costs related to the integration of the operations of Avis Europe and the acquisition of Payless. During the three months ended September 30, 2012, the Company incurred $11 million in transaction-related costs related to the integration of the operations of Avis Europe.

[4] During the nine months ended September 30, 2013, the Company incurred $37 million in transaction-related costs related to the integration of the operations of Avis Europe and costs related to the acquisition and integration of Zipcar and Payless. During the nine months ended September 30, 2012, the Company incurred $21 million in transaction-related costs related to the integration of the operations of Avis Europe.

[5] Includes unallocated corporate overhead and the elimination of transactions between segments.