Acquisitions (Details Textuals) (USD $)	3 Months Ended		9 Months Ended				9 Months Ended		9 Months Ended			9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 Hill Hire [Member]	Jun. 08, 2011 Hill Hire [Member] Vehicle Customers Trailer Lease	Sep. 30, 2012 Euroway Ltd. [Member]	Aug. 01, 2012 Euroway Ltd. [Member] Vehicle	Sep. 30, 2012 Other Acquisitions [Member]	Sep. 30, 2011 Other Acquisitions [Member]	Dec. 31, 2011 Other Acquisitions [Member]	Sep. 30, 2012 Other Acquisitions Completed in Prior Years [Member]	Sep. 30, 2011 Other Acquisitions Completed in Prior Years [Member]
Business Acquisition [Line Items]
Restructuring and other charges (recoveries), net	$ 74,000	$ 0	$ 8,081,000	$ 768,000
Acquisitions (Textuals) [Abstract]
Purchase Price						251,500,000		2,400,000			113,800,000
Number of full service lease vehicles						8,000		560
Business Acquisition Number Of Contract Maintenance Vehicles Acquired								800
Number of rental vehicles						5,700
Number of contractual customers acquired						400
Number of trailers included in fleet						9,700
Purchase Price Adjustment					1,800,000
Payments to Acquire Businesses	1,400,000	13,600,000	3,780,000	362,184,000			1,200,000		1,600,000	106,600,000		1,000,000	4,100,000
Business Acquisition, Contingent Consideration, Potential Cash Payment								478,000
Goodwill							6,200,000		28,400,000
Customer relationship intangibles							$ 2,800,000		$ 11,900,000