The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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-URI http://asc.fasb.org/extlink&oid=6508144

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-Name Accounting Standards Codification

-Glossary Net Income

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-Glossary Other Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=6519514

+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

- Definition

Tax effect of the gross appreciation or the gross loss, net of reclassification adjustment, in the value of the total unsold available-for-sale securities at the end of an accounting period.

+ References+ Details

- Definition

Adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency of the reporting entity, net of tax.

+ References

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+ Details

- Definition

Gross appreciation or the gross loss in value of the total of unsold available-for-sale securities during the period being reported (except when designated as a fair value hedge).

+ References

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- Definition

Appreciation or loss in value (before reclassification adjustment) of the total of unsold securities during the period being reported on, net of tax. Reclassification adjustments include: (1) the unrealized holding gain (loss), net of tax, at the date of the transfer for a debt security from the held-to-maturity category transferred into the available-for-sale category. Also includes the unrealized gain (loss) at the date of transfer for a debt security from the available-for-sale category transferred into the held-to-maturity category; (2) the unrealized gains (losses) realized upon the sale of securities, after tax; and (3) the unrealized gains (losses) realized upon the write-down of securities, after tax.

+ References

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+ Details

Comprehensive Income (Components Of Comprehensive Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 24, 2011	Jun. 25, 2011	Mar. 26, 2011	Dec. 25, 2010	Sep. 25, 2010	Jun. 26, 2010	Mar. 27, 2010	Dec. 31, 2011	Dec. 25, 2010	Dec. 26, 2009
Comprehensive Income [Abstract]
Net income attributable to Landstar System, Inc. and subsidiary	$ 32,632	$ 30,158	$ 29,598	$ 20,619	$ 24,099	$ 21,802	$ 24,437	$ 17,176	$ 113,007	$ 87,514	$ 70,395
Unrealized holding gains on available-for-sale investments									26	312	791
Income tax expense on unrealized holding gains on available-for-sale investments									(9)	(111)	(279)
Net unrealized holding gains on available-for-sale investments									17	201	512
Foreign currency translation gains (losses)									(171)	182	547
Comprehensive income attributable to Landstar System, Inc. and subsidiary									$ 112,853	$ 87,897	$ 71,454