Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
REVENUES	$ 2,808,376	$ 2,860,026
COST OF SALES	2,376,873	2,440,263
GROSS PROFIT	431,503	419,763
Selling, general and administrative expenses	327,708	324,347
Depreciation and amortization expense	16,997	16,342
INCOME (LOSS) FROM OPERATIONS	86,798	79,074
OTHER INCOME (EXPENSE):
Floorplan interest expense	(15,703)	(14,087)
Other interest expense, net	(18,919)	(18,820)
INCOME (LOSS) BEFORE INCOME TAXES	52,176	46,167
Benefit (provision) for income taxes	(13,528)	(10,353)
NET INCOME (LOSS)	$ 38,648	$ 35,814
BASIC EARNINGS (LOSS) PER SHARE	$ 2.09	$ 1.70
Weighted average common shares outstanding (in shares)	17,797	20,298
DILUTED EARNINGS (LOSS) PER SHARE	$ 2.08	$ 1.70
Weighted average common shares outstanding (in shares)	17,849	20,307
New vehicle retail sales
REVENUES	$ 1,414,485	$ 1,513,590
COST OF SALES	1,343,094	1,438,163
Used vehicle retail sales
REVENUES	819,203	780,570
COST OF SALES	771,394	737,075
Used vehicle wholesale sales
REVENUES	92,138	104,029
COST OF SALES	91,687	102,374
Parts and service sales
REVENUES	369,174	349,515
COST OF SALES	170,698	162,651
Finance, insurance and other, net
REVENUES	$ 113,376	$ 112,322