Annual report pursuant to Section 13 and 15(d)

Accumulated Other Comprehensive Income - Additional Information (Detail)

v3.3.1.900
Accumulated Other Comprehensive Income - Additional Information (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Accumulated Other Comprehensive Income [Line Items]      
Net gain on sales of securities $ 6,611 $ 2,011 $ 1,039
Recognized in earnings resulting from the redemption of investment securities 1,900 (498) 3,300
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Unrealized Investment Gain (Loss) [Member]      
Accumulated Other Comprehensive Income [Line Items]      
Net gain on sales of securities $ 6,600 $ 2,000 $ 1,000