Subsidiary Dividend Restrictions - Additional Information (Detail) (WNFIC [Member], USD $)	0 Months Ended	9 Months Ended
	May 20, 2014	Sep. 30, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Dividend rate as a percentage of net income		100.00%
Ordinary dividends payment description		The maximum amount of ordinary dividends that WNFIC can pay to shareholders in a rolling twelve month period is limited to the greater of 10% of statutory adjusted capital and surplus as shown on WNFIC's last annual statement on file with the superintendent or 100% of adjusted net income.
Payment of extraordinary dividends	$ 7,000,000	$ 7,000,000
Scenario, Forecast [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Payment of ordinary dividends		$ 0
Maximum [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Dividend rate as a percentage of net income		10.00%