Unaudited Condensed Consolidated Income Statements (USD $) In Millions, except Per Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
TOTAL REVENUE	$ 3,506.5	$ 3,273.9	$ 10,153.9	$ 9,214.8
TOTAL COST OF SALES	2,931.3	2,728.5	8,429.1	7,631.8
TOTAL GROSS PROFIT	575.2	545.4	1,724.8	1,583.0
Selling, general, and administrative expenses	411.4	402.9	1,236.7	1,159.4
Depreciation and amortization	20.9	18.7	62.7	57.2
Other expenses (income), net	(1.2)	2.9	(3.1)	4.5
OPERATING INCOME	144.1	120.9	428.5	361.9
Floorplan interest expense	(9.7)	(10.8)	(31.8)	(30.2)
Other interest expense	(16.4)	(16.1)	(48.6)	(39.8)
Loss on debt extinguishment	0	0	0	(19.6)
Interest income	0	0.3	0.6	0.8
Other losses, net	(2.4)	(0.7)	(0.2)	(1.1)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	115.6	93.6	348.5	272.0
INCOME TAX PROVISION	44.9	35.1	134.2	104.8
NET INCOME FROM CONTINUING OPERATIONS	70.7	58.5	214.3	167.2
Loss from discontinued operations, net of income taxes	0	(1.6)	(2.3)	(7.9)
NET INCOME	70.7	56.9	212.0	159.3
BASIC EARNINGS (LOSS) PER SHARE:
Continuing operations	$ 0.49	$ 0.40	$ 1.46	$ 1.05
Discontinued operations	$ 0.00	$ (0.01)	$ (0.02)	$ (0.05)
Net income	$ 0.49	$ 0.39	$ 1.44	$ 1.00
Weighted average common shares outstanding	144.4	147.5	146.9	160.0
DILUTED EARNINGS (LOSS) PER SHARE:
Continuing operations	$ 0.48	$ 0.39	$ 1.43	$ 1.04
Discontinued operations	$ 0.00	$ (0.01)	$ (0.02)	$ (0.05)
Net income	$ 0.48	$ 0.38	$ 1.42	$ 0.99
Weighted average common shares outstanding	147.0	149.6	149.5	161.4
COMMON SHARES OUTSTANDING, net of treasury stock	141.4	148.0	141.4	148.0
New Vehicle [Member]
TOTAL REVENUE	1,881.6	1,773.3	5,413.3	4,890.4
TOTAL COST OF SALES	1,743.4	1,661.4	5,013.1	4,566.7
TOTAL GROSS PROFIT	138.2	111.9	400.2	323.7
Used Vehicle [Member]
TOTAL REVENUE	911.9	812.4	2,630.6	2,327.7
TOTAL COST OF SALES	845.4	743.2	2,407.4	2,122.7
TOTAL GROSS PROFIT	66.5	69.2	223.2	205.0
Parts and Service [Member]
TOTAL REVENUE	578.0	564.1	1,720.0	1,648.9
TOTAL COST OF SALES	336.1	318.5	988.4	927.3
TOTAL GROSS PROFIT	241.9	245.6	731.6	721.6
Finance and Insurance, Net [Member]
TOTAL REVENUE	121.9	111.9	349.6	311.9
TOTAL GROSS PROFIT	121.9	111.9	349.6	311.9
Other Goods and Services [Member]
TOTAL REVENUE	13.1	12.2	40.4	35.9
TOTAL COST OF SALES	6.4	5.4	20.2	15.1
TOTAL GROSS PROFIT	$ 6.7	$ 6.8	$ 20.2	$ 20.8