Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Cash flows from operating activities:
Net income	$ 34,358	$ 48,237
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	67,815	53,196
Gain on sale of property and equipment	(19)	(136)
Stock-based compensation expense related to stock options and employee stock purchases	6,975	6,045
Provision (benefit) for deferred income tax expense	8,284	19,341
Excess tax benefits from stock-based compensation	(2,183)	(1,433)
Change in accounts receivable, net	(22,880)	6,019
Change in inventories	(46,446)	(49,735)
Change in prepaid expenses and other, net	3,117	7,999
Change in trade accounts payable	20,859	3,658
Draws on floor plan notes payable – trade, net	18,298	36,790
Change in accrued expenses	(10,378)	(40,982)
Net cash provided by operating activities	77,800	88,999
Cash flows from investing activities:
Acquisition of property and equipment	(122,999)	(130,057)
Proceeds from the sale of property and equipment	453	1,156
Business acquisitions	(63,188)	(36)
Change in other assets	(3,313)	(729)
Net cash (used in) investing activities	(189,047)	(129,666)
Cash flows from financing activities:
Draws on floor plan notes payable – non-trade, net	35,553	17,728
Proceeds from long-term debt	112,411	102,731
Principal payments on long-term debt	(64,911)	(55,212)
Principal payments on capital lease obligations	(10,211)	(7,963)
Excess tax benefits from stock-based compensation	2,183	1,433
Proceeds from issuance of shares relating to employee stock options and employee stock purchases	8,092	4,478
Common stock repurchased	(4,383)
Net cash provided by financing activities	78,734	63,195
Net (decrease) increase in cash and cash equivalents	(32,513)	22,528
Cash and cash equivalents, beginning of period	198,773	207,775
Cash and cash equivalents, end of period	166,260	230,303
Cash paid during the period for:
Interest	17,592	17,553
Income taxes, net of refunds	6,869	3,271
Noncash investing activities:
Assets acquired under capital leases	$ 5,872	$ 10,409