Short-Term Borrowings - Summary of Short-Term Borrowings (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Short-term Debt [Line Items]
Total	$ 500	$ 3,982
Weighted average interest rate	0.15%	0.18%
Federal Funds Purchased [Member]
Short-term Debt [Line Items]
Total	$ 500	$ 1,000
Repurchase Agreements [Member]
Short-term Debt [Line Items]
Total		$ 2,982
Short-term Debt [Member]
Short-term Debt [Line Items]
End of period interest rate	0.38%	0.14%