Fair Value Disclosures - Other Real Estate Owned (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Fair Value Disclosures [Abstract]
Carrying value of other real estate owned prior to re-measurement	$ 173	$ 351	$ 881
Write-downs included in gain (loss) on sale of other real estate owned	(46)	(95)	(135)
Other real estate owned, fair value	$ 127	$ 256	$ 746