Deposits (Additional Information) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Banking and Thrift [Abstract]
Demand Deposit Overdrafts Reclassified As Loan	$ 1.4	$ 2.2
Percentage of time deposits over total deposits	8.00%
Interest expense on time deposits of $100,000 or more	$ 2.2	$ 1.5	$ 1.7