Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Revenue	$ 4,084,577	$ 4,615,144	$ 3,646,364
Investment income	5,041	3,816	2,498
Costs and expenses:
Purchased transportation	3,127,474	3,569,961	2,805,109
Commissions to agents	342,226	378,002	297,410
Other operating costs, net of gains on asset sales/dispositions	37,274	31,803	28,687
Insurance and claims	80,319	75,677	62,545
Selling, general and administrative	158,953	188,212	170,583
Depreciation and amortization	44,468	43,570	40,560
Total costs and expenses	3,790,714	4,287,225	3,404,894
Operating income	298,904	331,735	243,968
Interest and debt expense	3,141	3,354	3,166
Income before income taxes	295,763	328,381	240,802
Income taxes	68,060	73,168	63,806
Net income	227,703	255,213	176,996
Less: Net loss attributable to noncontrolling interest	(17)	(68)	(92)
Net income attributable to Landstar System, Inc. and subsidiary	$ 227,720	$ 255,281	$ 177,088
Earnings per common share attributable to Landstar System, Inc. and subsidiary	$ 5.72	$ 6.19	$ 4.22
Diluted earnings per share attributable to Landstar System, Inc. and subsidiary	$ 5.72	$ 6.18	$ 4.21
Average number of shares outstanding:
Earnings per common share	39,786,000	41,273,000	41,938,000
Diluted earnings per share	39,786,000	41,310,000	42,024,000
Dividends per common share	$ 2.70	$ 0.63	$ 1.88