Quarterly report pursuant to Section 13 or 15(d)

Securities - Summary of Investment Securities Available for Sale (Detail)

v3.5.0.2
Securities - Summary of Investment Securities Available for Sale (Detail) - USD ($)
$ in Thousands
Sep. 30, 2016
Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost $ 537,820 $ 700,627
Gross Unrealized Gain 11,609 2,488
Gross Unrealized Loss 468 4,819
Estimated Fair Value 548,961 698,296
Municipal bonds-tax exempt [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 160,371 162,101
Gross Unrealized Gain 6,865 1,820
Gross Unrealized Loss 0 19
Estimated Fair Value 167,236 163,902
Municipal bonds-taxable [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 13,434 13,932
Gross Unrealized Gain 491 189
Gross Unrealized Loss 0 88
Estimated Fair Value 13,925 14,033
Corporate bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 5,012 5,017
Gross Unrealized Gain 0 0
Gross Unrealized Loss 1 24
Estimated Fair Value 5,011 4,993
Mutual funds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 22,916 22,916
Gross Unrealized Gain 280 0
Gross Unrealized Loss 87 163
Estimated Fair Value 23,109 22,753
Mortgage-backed securities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 239,569 286,450
Gross Unrealized Gain 3,778 392
Gross Unrealized Loss 102 2,461
Estimated Fair Value 243,245 284,381
Collateralized mortgage obligations [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 84,277 97,904
Gross Unrealized Gain 174 79
Gross Unrealized Loss 238 997
Estimated Fair Value 84,213 96,986
U.S. government agency securities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 7,499 48,478
Gross Unrealized Gain 20 0
Gross Unrealized Loss 0 656
Estimated Fair Value 7,519 47,822
SBA loan pool securities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 4,585 63,670
Gross Unrealized Gain 0 7
Gross Unrealized Loss 40 411
Estimated Fair Value 4,545 63,266
U.S. treasury securities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 157 159
Gross Unrealized Gain 1 1
Gross Unrealized Loss 0 0
Estimated Fair Value 158 160
Collateralized home equity conversion mortgages [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Estimated Fair Value $ 54,500 $ 58,600