Segment Reporting (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Share-based compensation expense	$ 20,905	$ 19,310	$ 18,864
Depreciation expense	1,040,259	957,141	939,677
Gains on vehicles sales, net	(126,824)	(96,175)	(89,108)
Defined benefit plan, lump sum settlement charge, pre tax	97,231	0	0
Amortization expense and other non-cash charges, net	47,263	56,389	49,209
Interest expense (income)	142,075	137,196	140,557
Capital expenditures paid	2,259,164	2,140,464	2,133,235
Total assets	9,675,986	9,103,782	8,318,979
Operating Segments [Member] | Fleet Management Solutions [Member]
Segment Reporting Information [Line Items]
Share-based compensation expense	4,895	4,979	5,359
Depreciation expense	1,011,227	926,724	910,352
Gains on vehicles sales, net	(126,410)	(96,011)	(89,075)
Defined benefit plan, lump sum settlement charge, pre tax	76,239
Amortization expense and other non-cash charges, net	19,936	19,071	15,567
Interest expense (income)	144,583	139,288	140,747
Capital expenditures paid	2,166,319	2,092,544	2,090,443
Total assets	8,818,816	8,309,149	7,556,509
Operating Segments [Member] | Supply Chain Solutions [Member]
Segment Reporting Information [Line Items]
Share-based compensation expense	4,381	4,934	4,433
Depreciation expense	28,847	29,560	28,275
Gains on vehicles sales, net	(414)	(164)	(33)
Defined benefit plan, lump sum settlement charge, pre tax	6,612
Amortization expense and other non-cash charges, net	1,825	3,640	2,768
Interest expense (income)	(2,327)	(1,864)	11
Capital expenditures paid	22,824	22,677	19,278
Total assets	898,196	869,074	807,935
Central Support Service [Member]
Segment Reporting Information [Line Items]
Share-based compensation expense	11,629	9,397	9,072
Depreciation expense	185	857	1,050
Gains on vehicles sales, net	0	0	0
Defined benefit plan, lump sum settlement charge, pre tax	14,380
Amortization expense and other non-cash charges, net	25,502	33,678	30,874
Interest expense (income)	(181)	(228)	(201)
Capital expenditures paid	70,021	25,243	23,514
Total assets	198,734	160,249	144,355
Eliminations [Member]
Segment Reporting Information [Line Items]
Share-based compensation expense	0	0	0
Depreciation expense	0	0	0
Gains on vehicles sales, net	0	0	0
Defined benefit plan, lump sum settlement charge, pre tax	0
Amortization expense and other non-cash charges, net	0	0	0
Interest expense (income)	0	0	0
Capital expenditures paid	0	0	0
Total assets	$ (239,760)	$ (234,690)	$ (189,820)