Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Sales revenue	$ 758,894	$ 582,857
Cost of revenue	631,023	481,261
Gross profit	127,871	101,596
Asset impairments	115	382
Selling, general and administrative	91,590	77,134
Operating income	31,967	19,988
Floor plan interest expense	(2,950)	(2,462)
Other interest expense	(2,747)	(3,292)
Other income, net	499	77
Income from continuing operations before income taxes	26,769	14,311
Income tax provision	(9,973)	(5,923)
Income from continuing operations, net of income tax	16,796	8,388
Income from discontinued operations, net of income tax		317
Net income	16,796	8,705
Basic income per share from continuing operations (in Dollars per share)	$ 0.65	$ 0.32
Basic income per share from discontinued operations (in Dollars per share)		$ 0.01
Basic net income per share (in Dollars per share)	$ 0.65	$ 0.33
Shares used in basic per share calculations (in Shares)	25,986	26,341
Diluted income per share from continuing operations (in Dollars per share)	$ 0.63	$ 0.31
Diluted income per share from discontinued operations (in Dollars per share)		$ 0.02
Diluted net income per share (in Dollars per share)	$ 0.63	$ 0.33
Shares used in diluted per share calculations (in Shares)	26,478	26,694
New Vehicle [Member]
Sales revenue	404,288	300,640
Cost of revenue	373,162	278,034
Used Vehicle Retail [Member]
Sales revenue	195,421	156,478
Cost of revenue	166,507	133,494
Used Vehicle Wholesale [Member]
Sales revenue	34,336	29,537
Cost of revenue	33,918	29,138
Finance And Insurance [Member]
Sales revenue	25,420	19,299
Service, Body And Parts [Member]
Sales revenue	86,448	73,761
Cost of revenue	44,855	38,000
Fleet And Other [Member]
Sales revenue	12,981	3,142
Cost of revenue	12,581	2,595
Segment, Continuing Operations [Member]
Depreciation and amortization	$ 4,199	$ 4,092