Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Net income attributable to Landstar System, Inc. and subsidiary	$ 61,100	$ 62,523	$ 124,417	$ 120,040
Other comprehensive income (loss):
Unrealized holding gains (losses) on available-for-sale investments, net of tax expense (benefit) of $494, ($233), $222 and ($42)	810	(153)	1,805	(883)
Foreign currency translation gains (losses)	571	(1,580)	1,125	(1,239)
Other comprehensive income (loss)	1,381	(1,733)	2,930	(2,122)
Comprehensive income attributable to Landstar System, Inc. and subsidiary	$ 62,481	$ 60,790	$ 127,347	$ 117,918