Goodwill and Other Intangible Assets (Changes in Goodwill) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011
Goodwill
Balance at the beginning of the period	$ 1,113,100,000		$ 1,049,600,000
Accumulated impairment losses at the beginning of the period	(721,000,000)		(721,000,000)
Net goodwill, balance at the beginning of the period	392,094,000		328,600,000
Goodwill acquired during the period	966,900,000		65,400,000
Adjustments to previously recorded purchase price allocation	(15,300,000)	[1]	(1,000,000)
Other changes during the period	(1,800,000)	[2]	(900,000)	[2]
Total changes in goodwill	949,800,000		63,500,000
Balance at the end of the period	2,062,900,000		1,113,100,000
Accumulated impairment losses at the end of the period	(721,000,000)		(721,000,000)
Net goodwill, balance at the end of the period	1,341,872,000		392,094,000
Car Rental
Goodwill
Balance at the beginning of the period	419,300,000		367,900,000
Accumulated impairment losses at the beginning of the period	(46,100,000)		(46,100,000)
Net goodwill, balance at the beginning of the period	373,200,000		321,800,000
Goodwill acquired during the period	884,900,000		53,100,000
Adjustments to previously recorded purchase price allocation	(15,300,000)	[1]	(900,000)
Other changes during the period	(1,400,000)	[2]	(800,000)	[2]
Total changes in goodwill	868,200,000		51,400,000
Balance at the end of the period	1,287,500,000		419,300,000
Accumulated impairment losses at the end of the period	(46,100,000)		(46,100,000)
Net goodwill, balance at the end of the period	1,241,400,000		373,200,000
Equipment Rental
Goodwill
Balance at the beginning of the period	693,800,000		681,700,000
Accumulated impairment losses at the beginning of the period	(674,900,000)		(674,900,000)
Net goodwill, balance at the beginning of the period	18,900,000		6,800,000
Goodwill acquired during the period	82,000,000		12,300,000
Adjustments to previously recorded purchase price allocation	0	[1]	(100,000)
Other changes during the period	(400,000)	[2]	(100,000)	[2]
Total changes in goodwill	81,600,000		12,100,000
Balance at the end of the period	775,400,000		693,800,000
Accumulated impairment losses at the end of the period	(674,900,000)		(674,900,000)
Net goodwill, balance at the end of the period	$ 100,500,000		$ 18,900,000

[1] Consists of deferred tax adjustments recorded during 2012.

[2] Primarily consists of changes resulting from disposals and the translation of foreign currencies at different exchange rates from the beginning of the period to the end of the period.