This item represents the pretax change in net unrealized holding gain (loss) on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 21

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

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Sales that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

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This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

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Fair Value of Financial Instruments (in thousands) Unobservable Inputs (Details) (USD $)	3 Months Ended	9 Months Ended
	Sep. 29, 2012 Short Term Maximum	Sep. 29, 2012 Short Term Maximum	Sep. 29, 2012 Long Term	Oct. 01, 2011 Long Term	Sep. 29, 2012 Level 3	Oct. 01, 2011 Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Change in net Unrealized Holding Gain (Loss) before Taxes	$ 100,000	$ 100,000
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning fair value of Long-term marketable securities					6,946,000	10,232,000
Fair value of securities sold or redeemed					(2,285,000)	(2,843,000)
Ending fair value of Long-term marketable securities					4,661,000	7,389,000
Realized gain on sale of securities			$ 400,000	$ 600,000