Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net income	$ 141,583	$ 139,062	$ 172,129
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	175,484	185,122	157,951
Loss (gain) on sale of property and equipment, net	102	(297)	105
Stock-based compensation expense related to employee stock options and employee stock purchases	19,005	18,059	15,606
Provision (benefit) for deferred income tax expense	22,989	5,997	(62,203)
Change in accounts receivable, net	19,831	(7,746)	(29,424)
Change in inventories	81,722	(255,040)	(147,453)
Change in prepaid expenses and other, net	(10,237)	1,907	(3,383)
Change in trade accounts payable	2,241	18,490	8,964
(Payments) draws on floor plan notes payable – trade, net	(26,579)	76,646	19,355
Change in customer deposits	6,512	8,833	8,932
Change in accrued expenses	(12,757)	24,331	12,158
Other, net	1,376	0	0
Net cash provided by operating activities	421,272	215,364	152,737
Cash flows from investing activities:
Acquisition of property and equipment	(293,493)	(238,260)	(209,917)
Proceeds from the sale of property and equipment	2,310	6,325	3,968
Business acquisitions	(10,168)	0	(2,180)
Purchase of equity method investment and call option	(22,499)	0	0
Proceeds from the sale of available for sale securities	0	6,375	325
Other	3,394	(1,683)	1,241
Net cash used in investing activities	(320,456)	(227,243)	(206,563)
Cash flows from financing activities:
(Payments) draws on floor plan notes payable – non-trade, net	(104)	167,812	112,261
Proceeds from long-term debt	210,043	156,751	152,563
Principal payments on long-term debt	(183,538)	(167,106)	(145,038)
Principal payments on finance lease obligations	(8,331)	(12,429)	(12,449)
Draws on line of credit	135,000	0	0
Payments on line of credit	(135,000)	0	0
Proceeds from issuance of shares relating to employee stock options and employee stock purchases	8,244	3,926	23,327
Payments of cash dividends	(18,317)	(9,332)	0
Common stock repurchased	(58,188)	(120,558)	(33,800)
Debt issuance costs	(731)	0	(523)
Net cash (used in) provided by financing activities	(50,922)	19,064	96,341
Net increase (decrease) in cash and cash equivalents	49,894	7,185	42,515
Cash and cash equivalents, beginning of year	131,726	124,541	82,026
Cash and cash equivalents, end of year	181,620	131,726	124,541
Supplemental disclosure of cash flow information:
Interest	57,373	42,752	34,149
Income taxes paid, net	42,440	28,674	31,323
Noncash investing and financing activities:
Assets acquired under finance leases	44,904	4,914	15,205
Common stock repurchased	99	0	0
Guaranty agreement	$ 5,025	$ 0	$ 0