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Insurance Activity - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2014 | Mar. 31, 2013 | Dec. 31, 2013 | Aug. 31, 2009
Effects of Reinsurance [Line Items] |  |  |  |
Quoted percentage to share base |  |  |  | 50.00%
Balances in the fair market reserve | $ 46.3 |  | $ 46.3 |
Decreased value of fair market reserve | $ 1.0 | $ 1.0 |  |
WMMRC [Member] |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |
Second loss layer risk percentage of range minimum |  |  |  | 5.00%
Second loss layer risk percentage of range maximum |  |  |  | 10.00%
First loss layer risk percentage of range minimum |  |  |  | 4.00%
First loss layer risk percentage of range maximum |  |  |  | 5.00%
Minimum period of reinsurance agreements | 5 years |  |  |
Maximum period of reinsurance agreements | 10 years |  |  |
WMMRC [Member] | Minimum [Member] |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |
Net of ceding commission, percentage |  |  |  | 25.00%
WMMRC [Member] | Maximum [Member] |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |
Net of ceding commission, percentage |  |  |  | 40.00%

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- Details
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- Definition Percentage of total reinsurance recoverables. + References No definition available. + Details
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- Definition Fair Market Value Reserve Balance + References No definition available. + Details
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- Definition First loss layer risk percentage of range maximum. + References No definition available. + Details
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- Definition First loss layer risk percentage of range minimum. + References No definition available. + Details
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- Definition Maximum period of reinsurance agreements. + References No definition available. + Details
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- Definition Minimum period of reinsurance agreements. + References No definition available. + Details
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- Definition Quoted percentage to share base. + References No definition available. + Details
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- Definition Second loss layer risk percentage of range maximum. + References No definition available. + Details
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- Definition Second loss layer risk percentage of range minimum. + References No definition available. + Details
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