Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2017	Jun. 25, 2016	Jul. 01, 2017	Jun. 25, 2016
Revenue	$ 870,434	$ 775,223	$ 1,651,342	$ 1,486,867
Investment income	608	363	1,022	743
Costs and expenses:
Purchased transportation	667,588	589,415	1,263,111	1,129,743
Commissions to agents	70,282	64,839	134,080	123,931
Other operating costs, net of gains on asset sales/dispositions	7,503	6,585	14,400	13,992
Insurance and claims	13,893	16,094	28,406	30,307
Selling, general and administrative	40,861	36,905	79,184	71,519
Depreciation and amortization	9,897	8,655	19,831	17,093
Total costs and expenses	810,024	722,493	1,539,012	1,386,585
Operating income	61,018	53,093	113,352	101,025
Interest and debt expense	819	888	1,902	1,777
Income before income taxes	60,199	52,205	111,450	99,248
Income taxes	22,689	19,891	41,557	37,750
Net income	$ 37,510	$ 32,314	$ 69,893	$ 61,498
Earnings per common share	$ 0.89	$ 0.77	$ 1.67	$ 1.45
Diluted earnings per share	$ 0.89	$ 0.76	$ 1.66	$ 1.45
Average number of shares outstanding:
Earnings per common share	41,935,000	42,235,000	41,907,000	42,315,000
Diluted earnings per share	42,010,000	42,357,000	42,004,000	42,424,000
Dividends per common share	$ 0.09	$ 0.08	$ 0.18	$ 0.16