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Reinsurance - Additional Information (Detail) | Dec. 31, 2011
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Number of companies that make up reinsurance recoverable | 91
Number of companies that make up majority of reinsurance recoverable | 14
Percent of reinsurance recoverable made up by majority of companies | 92.00%
Remaining companies rated A- or better by AM best | 7.00%
Percent of recoverable held with companies less than A- | 1.00%

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