Fair Value Measurement - Schedule of Assets Measured at Fair Value on Nonrecurring Basis (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other real estate owned and repossessed assets	$ 8,346	$ 5,825
Nonrecurring Fair Value Measurements [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans	3,405	6,363
Other real estate owned and repossessed assets	8,346	5,825
Significant Unobservable Inputs (Level 3) [Member] | Nonrecurring Fair Value Measurements [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans	3,405	6,363
Other real estate owned and repossessed assets	$ 8,346	$ 5,825
Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans, Appraisal adjustments	0.00%	0.00%
Impaired loans, Liquidation expenses	(1.50%)	(3.00%)
Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans, Appraisal adjustments	(70.00%)	(40.60%)
Impaired loans, Liquidation expenses	(8.00%)	(8.00%)
Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans, Appraisal adjustments	(36.60%)	(25.10%)
Impaired loans, Liquidation expenses	(4.60%)	(6.70%)