CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 29, 2012	Dec. 31, 2011	Dec. 25, 2010
Revenue	$ 2,793,420	$ 2,649,082	$ 2,400,170
Investment income	1,563	1,705	1,558
Costs and expenses:
Purchased transportation	2,129,345	2,007,102	1,824,308
Commissions to agents	218,363	210,088	181,405
Other operating costs	22,949	28,865	28,826
Insurance and claims	37,451	42,766	49,334
Selling, general and administrative	153,566	152,907	153,080
Depreciation and amortization	27,456	25,814	24,804
Total costs and expenses	2,589,130	2,467,542	2,261,757
Operating income	205,853	183,245	139,971
Interest and debt expense	3,104	3,112	3,623
Income before income taxes	202,749	180,133	136,348
Income taxes	72,968	67,188	49,766
Net income	129,781	112,945	86,582
Less: Net loss attributable to noncontrolling interest		(62)	(932)
Net income attributable to Landstar System, Inc. and subsidiary	$ 129,781	$ 113,007	$ 87,514
Earnings per common share attributable to Landstar System, Inc. and subsidiary	$ 2.78	$ 2.38	$ 1.77
Diluted earnings per share attributable to Landstar System, Inc. and subsidiary	$ 2.77	$ 2.38	$ 1.77
Average number of shares outstanding:
Earnings per common share	46,698,000	47,444,000	49,523,000
Diluted earnings per share	46,877,000	47,524,000	49,580,000
Dividends paid per common share	$ 0.73	$ 0.21	$ 0.19