Cash, Cash Equivalents and Investments (Details 6) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 29, 2012	Oct. 01, 2011	Sep. 29, 2012	Oct. 01, 2011	Dec. 31, 2011
Carrying value of non-marketable investments
Cost method	$ 5,054		$ 5,054		$ 6,157
Equity method	4,283		4,283		4,303
Total non-marketable investments	9,337		9,337		10,460
Net realized gains on the sale of non-marketable investments
Gains on sale of non-marketable investments	$ 0	$ 5,379	$ 0	$ 8,108

This item represents the aggregate carrying amount of all cost-method investments as reported on or included in the balance sheet. The original cost of the investments may differ from the aggregate carrying amount disclosed due to various adjustments such as: (i) dividends received in excess of earnings after the date of investment that are considered a return of investment and therefore recorded as reductions to cost of the investment, or (ii) a series of operating losses of an investee or other factors which may indicate that a decrease in value of the investment has occurred which is other than temporary and accordingly such decrease in value has been recognized.

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+ Details