Cash, Cash Equivalents and Investments (Details 4) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 28, 2013
Contractual maturity of marketable debt investments
Marketable debt securities, amortized cost, due in less than one year	$ 51,324
Marketable debt securities, amortized cost, due in one to three years	43,321
Marketable debt securities, amortized cost, total	94,645
Marketable debt securities, fair value, due in less than one year	51,358
Marketable debt securities, fair value, due in one to three years	43,353
Marketable debt securities, fair value, total	$ 94,711

Available for sale securities debt maturities year two through three amortized cost.

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Available for sale securities debt maturities year two through three fair value.

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Amount of available-for-sale debt securities at cost, net of adjustments, which include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount of available-for-sale debt securities at fair value maturing in the next fiscal year following the latest fiscal year.

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

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