Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
REVENUES:
New vehicle retail sales	$ 1,376,219	$ 1,080,710	$ 2,486,454	$ 1,993,305
Used vehicle retail sales	534,804	456,234	1,006,203	871,208
Used vehicle wholesale sales	83,316	73,134	157,867	139,991
Parts and service sales	260,950	220,313	498,460	433,414
Finance, insurance and other, net	79,821	65,435	149,958	122,653
Total revenues	2,335,110	1,895,826	4,298,942	3,560,571
COST OF SALES:
New vehicle retail sales	1,295,854	1,016,868	2,343,453	1,876,643
Used vehicle retail sales	491,299	417,388	922,422	795,965
Used vehicle wholesale sales	82,804	72,811	154,933	136,964
Parts and service sales	123,879	103,415	236,371	205,231
Total cost of sales	1,993,836	1,610,482	3,657,179	3,014,803
GROSS PROFIT	341,274	285,344	641,763	545,768
SELLING, GENERAL AND ADMINISTRATIVE EXPENSES	(251,159)	(214,327)	(484,592)	(413,439)
DEPRECIATION AND AMORTIZATION EXPENSE	(8,884)	(7,742)	(17,297)	(14,978)
ASSET IMPAIRMENTS	(609)	(187)	(609)	(288)
INCOME FROM OPERATIONS	80,622	63,088	139,265	117,063
OTHER EXPENSE:
Floorplan interest expense	(10,873)	(7,863)	(20,237)	(15,482)
Other interest expense, net	(9,570)	(9,190)	(18,812)	(18,230)
Other expense, net	0	0	(789)	0
INCOME BEFORE INCOME TAXES	60,179	46,035	99,427	83,351
PROVISION FOR INCOME TAXES	(22,791)	(17,410)	(39,921)	(31,609)
NET INCOME	$ 37,388	$ 28,625	$ 59,506	$ 51,742
BASIC EARNINGS PER SHARE	$ 1.53	$ 1.25	$ 2.49	$ 2.26
Weighted average common shares outstanding	23,315	21,650	22,796	21,640
DILUTED EARNINGS PER SHARE	$ 1.43	$ 1.20	$ 2.32	$ 2.18
Weighted average common shares outstanding	24,980	22,513	24,544	22,522
CASH DIVIDENDS PER COMMON SHARE	$ 0.16	$ 0.15	$ 0.31	$ 0.29