Summary of Significant Accounting Policies - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2015 $ / shares shares	Jun. 30, 2014 $ / shares shares
Summary Of Significant Accounting Policies [Line Items]
Number of stock options not considered in computing diluted earnings per share due to antidilutive nature	53,714	53,714
Weighted average price, option exercised | $ / shares	$ 10.34	$ 10.34
Number of operating divisions	2
Number of reportable operating segment	1