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New Pronouncements - Additional Information (Detail) (USD $) | 3 Months Ended | 9 Months Ended
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Sep. 29, 2013 | Sep. 30, 2012 | Sep. 29, 2013 | Sep. 30, 2012
New Accounting Pronouncement Or Change In Accounting Principle Retrospective Adjustments [Abstract] |  |  |  |
Reclassification from accumulated other comprehensive income to investment income | $ 20,000 | $ 340,000 | $ 103,000 | $ 1,411,000

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- Definition Other comprehensive income loss reclassification adjustment for realized gain loss on sale of securities included in net income, net of tax. + References No definition available. + Details
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- Details
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