Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
REVENUES:
New vehicle retail sales	$ 1,601,213	$ 1,521,246	$ 4,468,200	$ 4,256,146
Used vehicle retail sales	687,637	615,924	1,993,124	1,743,071
Used vehicle wholesale sales	100,483	100,347	302,186	284,491
Parts and service sales	303,557	291,816	888,939	844,340
Finance, insurance and other, net	107,679	97,115	307,454	270,901
Total revenues	2,800,569	2,626,448	7,959,903	7,398,949
COST OF SALES:
New vehicle retail sales	1,521,721	1,441,016	4,242,847	4,028,164
Used vehicle retail sales	641,055	571,613	1,854,361	1,610,293
Used vehicle wholesale sales	102,318	101,643	302,276	281,434
Parts and service sales	137,093	137,467	406,580	397,079
Total cost of sales	2,402,187	2,251,739	6,806,064	6,316,970
GROSS PROFIT	398,382	374,709	1,153,839	1,081,979
SELLING, GENERAL AND ADMINISTRATIVE EXPENSES	289,012	264,233	841,050	793,761
DEPRECIATION AND AMORTIZATION EXPENSE	11,811	10,746	35,441	31,424
ASSET IMPAIRMENTS	916	9,373	1,955	11,094
INCOME FROM OPERATIONS	96,643	90,357	275,393	245,700
OTHER EXPENSE:
Floorplan interest expense	(9,685)	(10,452)	(29,046)	(31,695)
Other interest expense, net	(13,922)	(13,246)	(42,061)	(36,326)
Loss on extinguishment of long-term debt	0	(22,790)	0	(46,403)
INCOME BEFORE INCOME TAXES	73,036	43,869	204,286	131,276
PROVISION FOR INCOME TAXES	(27,775)	(17,707)	(76,901)	(56,949)
NET INCOME	$ 45,261	$ 26,162	$ 127,385	$ 74,327
BASIC EARNINGS PER SHARE	$ 1.88	$ 1.07	$ 5.26	$ 3.06
Weighted average common shares outstanding	23,132	23,424	23,294	23,354
DILUTED EARNINGS PER SHARE	$ 1.88	$ 1.03	$ 5.26	$ 2.82
Weighted average common shares outstanding	23,137	24,432	23,298	25,363
CASH DIVIDENDS PER COMMON SHARE	$ 0.21	$ 0.17	$ 0.61	$ 0.51