Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2011	Dec. 25, 2010
Current Assets
Allowance on trade accounts receivable	$ 6,591	$ 5,324
Allowance on other receivables	5,384	5,511
Accumulated depreciation and amortization on operating property	$ 145,804	$ 137,830
Equity Landstar System, Inc. and subsidiary shareholders' equity:
Common stock, par value	$ 0.01	$ 0.01
Common stock, authorized shares	160,000,000	160,000,000
Common stock, issued shares	66,602,486	66,535,169
Treasury stock, shares	19,882,289	18,674,902