Restructuring (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended		60 Months Ended	66 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended	66 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended	66 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2012 employee	Jun. 30, 2012 employee	Mar. 31, 2012 employee	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011 employee	Jun. 30, 2012	Sep. 30, 2012 Car Rental	Sep. 30, 2011 Car Rental	Sep. 30, 2012 Car Rental	Sep. 30, 2011 Car Rental	Dec. 31, 2008 Car Rental location	Jun. 30, 2012 Car Rental	Sep. 30, 2012 Equipment Rental	Sep. 30, 2011 Equipment Rental	Sep. 30, 2012 Equipment Rental	Sep. 30, 2011 Equipment Rental	Dec. 31, 2008 Equipment Rental branch	Jun. 30, 2012 Equipment Rental	Jun. 30, 2012 Other	Sep. 30, 2012 Other reconciling items	Sep. 30, 2011 Other reconciling items	Sep. 30, 2012 Other reconciling items	Sep. 30, 2011 Other reconciling items	Sep. 30, 2012 Direct operating	Sep. 30, 2011 Direct operating	Sep. 30, 2012 Direct operating	Sep. 30, 2011 Direct operating	Sep. 30, 2012 Selling, general and administrative	Sep. 30, 2011 Selling, general and administrative	Sep. 30, 2012 Selling, general and administrative	Sep. 30, 2011 Selling, general and administrative	Sep. 30, 2012 Termination benefits	Sep. 30, 2011 Termination benefits	Sep. 30, 2012 Termination benefits	Sep. 30, 2011 Termination benefits	Sep. 30, 2012 Pension and Post Retirement expense	Sep. 30, 2011 Pension and Post Retirement expense	Sep. 30, 2012 Pension and Post Retirement expense	Sep. 30, 2011 Pension and Post Retirement expense	Sep. 30, 2012 Consultant costs	Sep. 30, 2011 Consultant costs	Sep. 30, 2012 Consultant costs	Sep. 30, 2011 Consultant costs	Sep. 30, 2012 Asset writedowns	Sep. 30, 2011 Asset writedowns	Sep. 30, 2012 Asset writedowns	Sep. 30, 2011 Asset writedowns	Sep. 30, 2012 Facility closure and lease obligation costs	Sep. 30, 2011 Facility closure and lease obligation costs	Sep. 30, 2012 Facility closure and lease obligation costs	Sep. 30, 2011 Facility closure and lease obligation costs	Sep. 30, 2012 Facility closures	Sep. 30, 2012 Relocation costs and temporary labor costs	Sep. 30, 2011 Relocation costs and temporary labor costs	Sep. 30, 2012 Relocation costs and temporary labor costs	Sep. 30, 2011 Relocation costs and temporary labor costs	Sep. 30, 2012 Other	Sep. 30, 2011 Other	Sep. 30, 2012 Other	Sep. 30, 2011 Other
Restructuring details
Charges incurred					$ 27.0																															$ 16.5				$ 0				$ 0.7																	$ 9.8
Number of off-airport locations closed													250
Number of branches in U.S. equipment rental segment closed																			22
Number of employees impacted	240	280	65				8,960
Restructuring charges incurred to date								557.5						273.5						229.5	54.5
Restructuring charges	1.5			1.9	27.0	40.4			0.2	2.8	17.2	7.3			1.3	(0.9)	8.1	32.7				0	0	1.7	0.4	3.7	0.7	18.3	35.3	(2.2)	1.2	8.7	5.1	0.3	2.4	16.5	6.8	0	0	0	0.3	0.1	0.3	0.7	0.6	0	(0.5)	2.7	22.8	0.9	(0.4)	6.6	9.6		0.1	0.1	0.1	0.1	0.1	0	0.4	0.2
Expected duration for payment of restructuring obligations (in months)																																		12 months		12 months
Restructuring reserve
Balance at beginning of period			21.6		21.6																															9.1				0.2				0.6																	11.7
Charges incurred	1.5			1.9	27.0	40.4			0.2	2.8	17.2	7.3			1.3	(0.9)	8.1	32.7				0	0	1.7	0.4	3.7	0.7	18.3	35.3	(2.2)	1.2	8.7	5.1	0.3	2.4	16.5	6.8	0	0	0	0.3	0.1	0.3	0.7	0.6	0	(0.5)	2.7	22.8	0.9	(0.4)	6.6	9.6		0.1	0.1	0.1	0.1	0.1	0	0.4	0.2
Cash payments					(18.5)																															(14.0)				0				(0.5)																	(4.0)
Other					9.3																															0.3				0				0.1				(2.7)						(6.4)							(8.9)
Balance at end of period	$ 20.8				$ 20.8		$ 21.6																											$ 11.3		$ 11.3		$ 0.2		$ 0.2		$ 0.7		$ 0.7															$ 8.6		$ 8.6