Summary of Stock Dividends Declared (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2013
Equity [Abstract]
Dividends Payable, Date Declared	Mar. 05, 2014
Dividends Payable Date Of Record Day Month And Year	Mar. 14, 2014
Dividends Payable, Date to be Paid	Mar. 28, 2014
Dividends Paid Amount Per Share	0.50%
Common stock, shares outstanding	58,115,000	58,228,000	37,422,753
Total Stock Dividends Declared	$ 193,032