Fair Value (Details 1) (USD $) In Thousands, unless otherwise specified	Jun. 29, 2012	Dec. 31, 2011
Maturities of short-term investments
Less than one year	$ 66,660	$ 43,470
Due in 1-2 years	18,695	27,384
Total short-term investments	$ 85,355	$ 70,854

Amount of debt securities categorized neither as held-to-maturity nor trading.

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+ Details