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New Pronouncements - Additional Information (Detail) (USD $) | 3 Months Ended | 6 Months Ended
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Jun. 30, 2013 | Jul. 01, 2012 | Jun. 30, 2013 | Jul. 01, 2012
New Accounting Pronouncement or Change in Accounting Principle, Retrospective Adjustments [Abstract] |  |  |  |
Reclassification from accumulated other comprehensive income to investment income | $ 52,000 | $ 977,000 | $ 83,000 | $ 1,071,000

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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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