Servicing Asset - Analysis of Servicing Asset (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Transfers and Servicing [Abstract]
Balance at beginning of year	$ 701	$ 4,178	$ 4,568
Acquired	214
Capitalized mortgage servicing rights		286	995
Amortization	(245)	(1,016)	(1,385)
Mortgage servicing rights sold	(81)	(2,747)
Balance at end of year	$ 589	$ 701	$ 4,178