Consolidated Statements of Income and Comprehensive Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues:
New and used commercial vehicle sales	$ 819,028	$ 698,838	$ 2,230,969	$ 2,004,236
Aftermarket products and services sales	375,835	336,459	1,092,540	1,007,063
Lease and rental	54,630	52,452	158,922	155,491
Finance and insurance	4,771	4,870	13,092	14,206
Other	3,195	3,422	10,256	12,347
Total revenue	1,257,459	1,096,041	3,505,779	3,193,343
Cost of products sold:
New and used commercial vehicle sales	754,762	653,992	2,061,135	1,868,983
Aftermarket products and services sales	237,452	214,916	693,910	642,678
Lease and rental	45,197	45,817	133,707	136,618
Total cost of products sold	1,037,411	914,725	2,888,752	2,648,279
Gross profit	220,048	181,316	617,027	545,064
Selling, general and administrative expense	159,281	142,280	469,037	450,812
Depreciation and amortization expense	12,438	13,014	37,374	38,482
Gain on sale of assets	107	1,566	76	1,571
Operating income	48,436	27,588	110,692	57,341
Interest expense, net	3,101	3,285	8,716	11,287
Income before taxes	45,335	24,303	101,976	46,054
Provision for income taxes	15,551	9,423	35,714	17,962
Net income	$ 29,784	$ 14,880	$ 66,262	$ 28,092
Earnings per common share:
Basic (in dollars per share)	$ 0.75	$ 0.38	$ 1.68	$ 0.70
Diluted (in dollars per share)	$ 0.72	$ 0.37	$ 1.62	$ 0.69
Weighted average shares outstanding:
Basic (in shares)	39,825	39,617	39,560	40,138
Diluted (in shares)	41,146	40,274	40,830	40,698
Comprehensive income	$ 29,784	$ 14,889	$ 66,548	$ 28,111