Securities - Summary of Amortized Cost and Fair Value of Debt Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Available-for-sale
Due in one year or less, Amortized Cost	$ 10,156
Due after one through five years, Amortized Cost	21,491
Due after five through ten years, Amortized Cost	24,500
Due after ten years, Amortized Cost	64,893
Total debt securities available-for-sale, Amortized Cost	121,040
Due in one year or less, Fair Value	10,174
Due after one through five years, Fair Value	21,696
Due after five through ten years, Fair Value	24,758
Due after ten years, Fair Value	65,549
Total debt securities available-for-sale, Fair Value	122,177
Held-to-maturity
Due in one year or less, Amortized Cost	0
Due after one through five years, Amortized Cost	0
Due after five through ten years, Amortized Cost	5,794
Due after ten years, Amortized cost	21,231
Amortized Cost, Held to maturity	27,025	$ 33,819
Due in one year or less, Fair Value	0
Due after one through five years, Fair Value	0
Due after five through ten years, Fair Value	5,997
Due after ten years, Fair Value	21,663
Total debt securities held-to-maturity, Fair Value	$ 27,660	$ 34,011