Segment Reporting (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Segment Reporting, Other Significant Reconciling Item, Consolidated [Abstract]
Share-based compensation	$ 18,864	$ 17,423	$ 16,543
Depreciation expense	939,677	872,262	833,841
Gains on vehicle sales, net	(89,108)	(62,879)	(28,727)
Other non-cash charges (credits), net	49,209	39,928	40,900
Interest expense (income)	140,557	133,164	129,994
Capital expenditures paid	2,133,235	1,698,589	1,070,092
Total assets	8,318,979	7,617,835	6,652,374
Fleet Management Solutions [Member]
Segment Reporting, Other Significant Reconciling Item, Consolidated [Abstract]
Share-based compensation	5,359	5,388	5,011
Depreciation expense	910,352	842,094	812,588
Gains on vehicle sales, net	(89,075)	(62,496)	(28,765)
Other non-cash charges (credits), net	15,567	16,271	19,351
Interest expense (income)	140,747	133,245	130,742
Capital expenditures paid	2,090,443	1,653,425	1,043,280
Total assets	7,556,509	6,815,404	5,944,971
Supply Chain Solutions [Member]
Segment Reporting, Other Significant Reconciling Item, Consolidated [Abstract]
Share-based compensation	4,433	4,312	3,430
Depreciation expense	28,275	29,118	20,285
Gains on vehicle sales, net	(33)	(383)	38
Other non-cash charges (credits), net	2,768	3,214	1,021
Interest expense (income)	11	(74)	(759)
Capital expenditures paid	19,278	30,209	16,345
Total assets	807,935	827,169	791,791
Central Support Service [Member]
Segment Reporting, Other Significant Reconciling Item, Consolidated [Abstract]
Share-based compensation	9,072	7,723	8,102
Depreciation expense	1,050	1,050	968
Gains on vehicle sales, net	0	0	0
Other non-cash charges (credits), net	30,874	20,443	20,528
Interest expense (income)	(201)	(7)	11
Capital expenditures paid	23,514	14,955	10,467
Total assets	144,355	198,476	106,906
Eliminations [Member]
Segment Reporting, Other Significant Reconciling Item, Consolidated [Abstract]
Share-based compensation	0	0	0
Depreciation expense	0	0	0
Gains on vehicle sales, net	0	0	0
Other non-cash charges (credits), net	0	0	0
Interest expense (income)	0	0	0
Capital expenditures paid	0	0	0
Total assets	$ (189,820)	$ (223,214)	$ (191,294)