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