Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Revenue	$ 1,182,786	$ 870,434	$ 2,230,712	$ 1,651,342
Investment income	891	608	1,752	1,022
Costs and expenses:
Purchased transportation	916,940	667,588	1,727,237	1,263,111
Commissions to agents	94,399	70,282	176,524	134,080
Other operating costs, net of gains on asset sales/dispositions	7,606	7,503	15,210	14,400
Insurance and claims	21,539	13,893	38,899	28,406
Selling, general and administrative	48,998	40,861	94,249	79,184
Depreciation and amortization	10,769	9,897	21,766	19,831
Total costs and expenses	1,100,251	810,024	2,073,885	1,539,012
Operating income	83,426	61,018	158,579	113,352
Interest and debt expense	839	819	1,639	1,902
Income before income taxes	82,587	60,199	156,940	111,450
Income taxes	20,095	22,689	36,975	41,557
Net income	62,492	37,510	119,965	69,893
Less: Net loss attributable to noncontrolling interest	(31)		(75)
Net income attributable to Landstar System, Inc. and subsidiary	$ 62,523	$ 37,510	$ 120,040	$ 69,893
Earnings per common share attributable to Landstar System, Inc. and subsidiary	$ 1.51	$ 0.89	$ 2.88	$ 1.67
Diluted earnings per share attributable to Landstar System, Inc. and subsidiary	$ 1.51	$ 0.89	$ 2.87	$ 1.66
Average number of shares outstanding:
Earnings per common share	41,450,000	41,935,000	41,744,000	41,907,000
Diluted earnings per share	41,491,000	42,010,000	41,795,000	42,004,000
Dividends per common share	$ 0.15	$ 0.09	$ 0.30	$ 0.18