Quarterly report pursuant to Section 13 or 15(d)

Securities - Available for Sale Securities, Continuous Unrealized Loss Position, Fair value (Detail)

v3.5.0.2
Securities - Available for Sale Securities, Continuous Unrealized Loss Position, Fair value (Detail)
$ in Thousands
 6 Months Ended 12 Months Ended
Jun. 30, 2016
USD ($)
Security
Dec. 31, 2015
USD ($)
Security
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 170 $ 2,628
Available-for-Sale Within One Year, Estimated Fair Value $ 59,163 $ 359,531
Available-for-Sale Within One Year, Number of Securities | Security 20 104
Available-for-Sale More than One Year, Gross Unrealized Loss $ 286 $ 2,191
Available-for-Sale More than One Year, Estimated Fair Value $ 45,251 $ 87,120
Available-for-Sale More than One Year, Number of Securities | Security 19 36
Available-for-Sale, Gross Unrealized Loss $ 456 $ 4,819
Available-for-Sale, Estimated Fair Value $ 104,414 $ 446,651
Available-for-Sale, Number of Securities | Security 39 140
Municipal bonds-tax exempt [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 0 $ 19
Available-for-Sale Within One Year, Estimated Fair Value $ 0 $ 8,922
Available-for-Sale Within One Year, Number of Securities | Security 0 6
Available-for-Sale More than One Year, Gross Unrealized Loss $ 0 $ 0
Available-for-Sale More than One Year, Estimated Fair Value $ 0 $ 0
Available-for-Sale More than One Year, Number of Securities | Security 0 0
Available-for-Sale, Gross Unrealized Loss $ 0 $ 19
Available-for-Sale, Estimated Fair Value $ 0 $ 8,922
Available-for-Sale, Number of Securities | Security 0 6
Municipal bonds-taxable [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 0 $ 88
Available-for-Sale Within One Year, Estimated Fair Value $ 0 $ 7,106
Available-for-Sale Within One Year, Number of Securities | Security 0 4
Available-for-Sale More than One Year, Gross Unrealized Loss $ 0 $ 0
Available-for-Sale More than One Year, Estimated Fair Value $ 0 $ 0
Available-for-Sale More than One Year, Number of Securities | Security 0 0
Available-for-Sale, Gross Unrealized Loss $ 0 $ 88
Available-for-Sale, Estimated Fair Value $ 0 $ 7,106
Available-for-Sale, Number of Securities | Security 0 4
Mutual funds [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 0 $ 66
Available-for-Sale Within One Year, Estimated Fair Value $ 0 $ 21,820
Available-for-Sale Within One Year, Number of Securities | Security 0 3
Available-for-Sale More than One Year, Gross Unrealized Loss $ 85 $ 97
Available-for-Sale More than One Year, Estimated Fair Value $ 941 $ 928
Available-for-Sale More than One Year, Number of Securities | Security 3 3
Available-for-Sale, Gross Unrealized Loss $ 85 $ 163
Available-for-Sale, Estimated Fair Value $ 941 $ 22,748
Available-for-Sale, Number of Securities | Security 3 6
Collateralized mortgage obligations [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 10 $ 335
Available-for-Sale Within One Year, Estimated Fair Value $ 12,778 $ 48,970
Available-for-Sale Within One Year, Number of Securities | Security 6 18
Available-for-Sale More than One Year, Gross Unrealized Loss $ 81 $ 662
Available-for-Sale More than One Year, Estimated Fair Value $ 13,879 $ 32,964
Available-for-Sale More than One Year, Number of Securities | Security 7 13
Available-for-Sale, Gross Unrealized Loss $ 91 $ 997
Available-for-Sale, Estimated Fair Value $ 26,657 $ 81,934
Available-for-Sale, Number of Securities | Security 13 31
Mortgage-backed securities [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 43 $ 1,734
Available-for-Sale Within One Year, Estimated Fair Value $ 10,746 $ 193,931
Available-for-Sale Within One Year, Number of Securities | Security 4 52
Available-for-Sale More than One Year, Gross Unrealized Loss $ 34 $ 727
Available-for-Sale More than One Year, Estimated Fair Value $ 10,912 $ 21,659
Available-for-Sale More than One Year, Number of Securities | Security 3 9
Available-for-Sale, Gross Unrealized Loss $ 77 $ 2,461
Available-for-Sale, Estimated Fair Value $ 21,658 $ 215,590
Available-for-Sale, Number of Securities | Security 7 61
U.S. government agency securities [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 0 $ 201
Available-for-Sale Within One Year, Estimated Fair Value $ 0 $ 23,289
Available-for-Sale Within One Year, Number of Securities | Security 0 8
Available-for-Sale More than One Year, Gross Unrealized Loss $ 0 $ 455
Available-for-Sale More than One Year, Estimated Fair Value $ 0 $ 24,533
Available-for-Sale More than One Year, Number of Securities | Security 0 8
Available-for-Sale, Gross Unrealized Loss $ 0 $ 656
Available-for-Sale, Estimated Fair Value $ 0 $ 47,822
Available-for-Sale, Number of Securities | Security 0 16
SBA loan pool securities [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 117 $ 161
Available-for-Sale Within One Year, Estimated Fair Value $ 35,639 $ 50,499
Available-for-Sale Within One Year, Number of Securities | Security 10 12
Available-for-Sale More than One Year, Gross Unrealized Loss $ 73 $ 250
Available-for-Sale More than One Year, Estimated Fair Value $ 14,518 $ 7,036
Available-for-Sale More than One Year, Number of Securities | Security 5 3
Available-for-Sale, Gross Unrealized Loss $ 190 $ 411
Available-for-Sale, Estimated Fair Value $ 50,157 $ 57,535
Available-for-Sale, Number of Securities | Security 15 15
Corporate bonds [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 0 $ 24
Available-for-Sale Within One Year, Estimated Fair Value $ 0 $ 4,994
Available-for-Sale Within One Year, Number of Securities | Security 0 1
Available-for-Sale More than One Year, Gross Unrealized Loss $ 13 $ 0
Available-for-Sale More than One Year, Estimated Fair Value $ 5,001 $ 0
Available-for-Sale More than One Year, Number of Securities | Security 1 0
Available-for-Sale, Gross Unrealized Loss $ 13 $ 24
Available-for-Sale, Estimated Fair Value $ 5,001 $ 4,994
Available-for-Sale, Number of Securities | Security 1 1