Long-Term Borrowings and Subordinated Debt - Schedule of Annual Maturities and Average Interest Rate of Long-Term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Debt Disclosure [Abstract]
2016 Balance	$ 102,330
2017 Balance	2,412
2018 Balance	2,496
2019 Balance	2,514
2020 Balance	2,004
Thereafter Balance	5,287
Total Long-term Balance	$ 117,043	$ 19,442	$ 21,810
2016 Average Rate	0.52%
2017 Average Rate	3.52%
2018 Average Rate	3.60%
2019 Average Rate	3.13%
2020 Average Rate	3.22%
Thereafter Average Rate	1.85%
Total Average Rate	0.81%