Short-Term Investments - Maturities of Short-Term Investments (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 29, 2013	Dec. 31, 2012
Investments Debt And Equity Securities [Abstract]
Less than one year	$ 84,402	$ 76,779
Due in 1-2 years	25,388	27,727
Total short-term investments, Estimated Fair Value	$ 109,790	$ 104,506

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

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