Annual report pursuant to Section 13 and 15(d)

Securities - Schedule of Amortized Cost and Estimated Fair Value of Investment Securities by Contractual Maturity (Detail)

v3.6.0.2
Securities - Schedule of Amortized Cost and Estimated Fair Value of Investment Securities by Contractual Maturity (Detail) - USD ($)
$ in Thousands
Dec. 31, 2016
Dec. 31, 2015
Amortized Cost    
Within one year $ 337  
Over one year through five years 78,893  
Over five years through ten years 212,719  
Over ten years 229,104  
Amortized Cost 521,053 $ 700,627
Estimated Fair Value    
Within one year 337  
Over one year through five years 78,747  
Over five years through ten years 211,025  
Over ten years 226,855  
Total 516,964 698,296
Collateralized mortgage obligations [Member]    
Amortized Cost    
Amortized Cost 77,447 97,904
Estimated Fair Value    
Total 76,451 96,986
Mortgage-backed securities [Member]    
Amortized Cost    
Amortized Cost 230,489 286,450
Estimated Fair Value    
Total $ 229,630 $ 284,381