Guarantor And Non-Guarantor Consolidating Condensed Financial Statements (Consolidating Condensed Statements Of Comprehensive Income) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Supplemental Guarantor Financial Information [Line Items]
Short Term Debt And Current Portion Of Long Term Debt	$ 29		$ 57
Revenues
Vehicle rental	1,217	1,168
Other	474	455
Net revenues	1,691	1,623
Expenses
Operating	931	893
Vehicle depreciation and lease charges, net	386	318
Selling, general and administrative	224	219
Vehicle interest, net	57	74
Non-vehicle related depreciation and amortization	34	32
Interest expense	58	73
Intercompany Interest Expense Income	0	0
Early extinguishment of debt	40	27
Restructuring expense	10	7
Transaction-related costs	8	6
Total expenses	1,748	1,649
Interest expense related to corporate debt, net:
Income (loss) before income taxes and equity in earnings of subsidiaries	(57)	(26)
Provision for (benefit from) income taxes	(11)	(3)
Net loss	(46)	(23)
Comprehensive income (loss)	(69)	21
Parent [Member]
Revenues
Other		0
Net revenues		0
Expenses
Operating	2	(1)
Vehicle depreciation and lease charges, net	0	0
Selling, general and administrative	9	5
Vehicle interest, net	0	0
Non-vehicle related depreciation and amortization	0	0
Interest expense	1	3
Intercompany Interest Expense Income	(3)	(7)
Early extinguishment of debt	39	18
Restructuring expense	0	0
Transaction-related costs	0	3
Total expenses	48	21
Interest expense related to corporate debt, net:
Income (loss) before income taxes and equity in earnings of subsidiaries	(48)	(21)
Provision for (benefit from) income taxes	(4)	(1)
Equity in earnings (loss) of subsidiaries	(2)	(3)
Net loss	(46)	(23)
Comprehensive income (loss)		21
Subsidiary Issuers [Member]
Supplemental Guarantor Financial Information [Line Items]
Short Term Debt And Current Portion Of Long Term Debt	15		13
Expenses
Operating	1	6
Vehicle depreciation and lease charges, net	0	0
Selling, general and administrative	1	0
Vehicle interest, net	0	0
Non-vehicle related depreciation and amortization	0	0
Interest expense	54	64
Intercompany Interest Expense Income	(11)	(81)
Early extinguishment of debt	1	9
Restructuring expense	0	0
Transaction-related costs	4	0
Total expenses	50	(2)
Interest expense related to corporate debt, net:
Income (loss) before income taxes and equity in earnings of subsidiaries	(50)	2
Provision for (benefit from) income taxes	(20)	3
Equity in earnings (loss) of subsidiaries	28	(2)
Net loss	(2)	(3)
Comprehensive income (loss)	(25)	41
Guarantor Subsidiaries [Member]
Supplemental Guarantor Financial Information [Line Items]
Short Term Debt And Current Portion Of Long Term Debt	3		3
Revenues
Vehicle rental	837	786
Other	246	235
Net revenues	1,083	1,021
Expenses
Operating	558	537
Vehicle depreciation and lease charges, net	260	197
Selling, general and administrative	131	137
Vehicle interest, net	42	61
Non-vehicle related depreciation and amortization	22	19
Interest expense	0	0
Intercompany Interest Expense Income	3	74
Early extinguishment of debt	0	0
Restructuring expense	6	0
Transaction-related costs	1	0
Total expenses	1,023	1,025
Interest expense related to corporate debt, net:
Income (loss) before income taxes and equity in earnings of subsidiaries	60	(4)
Provision for (benefit from) income taxes	14	(2)
Equity in earnings (loss) of subsidiaries	(18)	0
Net loss	28	(2)
Comprehensive income (loss)	2	42
Subsidiaries Non Guarantor [Member]
Supplemental Guarantor Financial Information [Line Items]
Short Term Debt And Current Portion Of Long Term Debt	11		41
Non-Guarantor Subsidiaries [Member]
Revenues
Vehicle rental	380	382
Other	526	474
Net revenues	906	856
Expenses
Operating	370	351
Vehicle depreciation and lease charges, net	243	212
Selling, general and administrative	83	77
Vehicle interest, net	58	75
Non-vehicle related depreciation and amortization	12	13
Interest expense	3	6
Intercompany Interest Expense Income	11	14
Early extinguishment of debt	0	0
Restructuring expense	4	7
Transaction-related costs	3	3
Total expenses	787	758
Interest expense related to corporate debt, net:
Income (loss) before income taxes and equity in earnings of subsidiaries	119	98
Provision for (benefit from) income taxes	(1)	(3)
Net loss	120	101
Comprehensive income (loss)	95	146
Eliminations [Member]
Revenues
Other	(298)	(254)
Net revenues	(298)	(254)
Expenses
Operating	0	0
Vehicle depreciation and lease charges, net	(117)	(91)
Selling, general and administrative	0	0
Vehicle interest, net	(43)	(62)
Non-vehicle related depreciation and amortization	0	0
Interest expense	0	0
Intercompany Interest Expense Income	0	0
Early extinguishment of debt	0	0
Restructuring expense	0	0
Transaction-related costs	0	0
Total expenses	(160)	(153)
Interest expense related to corporate debt, net:
Income (loss) before income taxes and equity in earnings of subsidiaries	(138)	(101)
Equity in earnings (loss) of subsidiaries	(8)	5
Net loss	(146)	(96)
Comprehensive income (loss)	$ (72)	$ (229)