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Quarterly Financial Data (Unaudited) - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified | 0 Months Ended | 3 Months Ended
--- | --- | ---
Nov. 14, 2013 | Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract] |  |
Decrease in underwriting and other operating costs | $ 1.5 | $ 1.7
Increased income tax expense | 0.5 | 0.6
Net income statement impact | $ 1.0 | $ 1.1
Net income statement impact per share | $ 0.05 | $ 0.06

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- Details
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