Fair Value (Details 1) (USD $) In Thousands	Jul. 01, 2011	Dec. 31, 2010
Maturities of short-term investments
Less than one year	$ 35,890	$ 21,174
Due in 1-2 years	7,736	2,664
Due in 3-30 years	20,302	0
Total	$ 63,928	$ 23,838

For an unclassified balance sheet, total of debt securities categorized neither as held-to-maturity nor trading.

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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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+ Details