Quarterly report pursuant to Section 13 or 15(d)

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

v3.2.0.727
Securities - Available for Sale Securities, Continuous Unrealized Loss Position, Fair value (Detail)
$ in Thousands
 6 Months Ended 12 Months Ended
Jun. 30, 2015
USD ($)
Security
Dec. 31, 2014
USD ($)
Security
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 1,210 $ 833
Available-for-Sale Within One Year, Estimated Fair Value $ 199,627 $ 276,192
Available-for-Sale Within One Year, Number of Securities | Security 63 60
Available-for-Sale More than One Year, Holding Period, Gross Unrealized Loss $ 2,702 $ 4,133
Available-for-Sale More than One Year, Holding Period, Estimated Fair Value $ 101,766 $ 184,458
Available-for-Sale More than One Year, Holding Period, Number of Securities | Security 40 73
Available-for-Sale, Gross Unrealized Loss $ 3,912 $ 4,966
Available-for-Sale, Estimated Fair Value $ 301,393 $ 460,650
Available-for-Sale, Number of Securities | Security 103 133
Municipal bonds-taxable [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 46 $ 0
Available-for-Sale Within One Year, Estimated Fair Value $ 6,086 $ 0
Available-for-Sale Within One Year, Number of Securities | Security 5 0
Available-for-Sale More than One Year, Holding Period, Gross Unrealized Loss $ 0 $ 91
Available-for-Sale More than One Year, Holding Period, Estimated Fair Value $ 0 $ 5,538
Available-for-Sale More than One Year, Holding Period, Number of Securities | Security 0 5
Available-for-Sale, Gross Unrealized Loss $ 46 $ 91
Available-for-Sale, Estimated Fair Value $ 6,086 $ 5,538
Available-for-Sale, Number of Securities | Security 5 5
Collateralized mortgage obligations [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 114 $ 350
Available-for-Sale Within One Year, Estimated Fair Value $ 28,201 $ 78,191
Available-for-Sale Within One Year, Number of Securities | Security 8 21
Available-for-Sale More than One Year, Holding Period, Gross Unrealized Loss $ 546 $ 724
Available-for-Sale More than One Year, Holding Period, Estimated Fair Value $ 28,654 $ 33,308
Available-for-Sale More than One Year, Holding Period, Number of Securities | Security 12 13
Available-for-Sale, Gross Unrealized Loss $ 660 $ 1,074
Available-for-Sale, Estimated Fair Value $ 56,855 $ 111,499
Available-for-Sale, Number of Securities | Security 20 34
Mortgage-backed securities [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 595 $ 288
Available-for-Sale Within One Year, Estimated Fair Value $ 94,908 $ 102,704
Available-for-Sale Within One Year, Number of Securities | Security 32 21
Available-for-Sale More than One Year, Holding Period, Gross Unrealized Loss $ 785 $ 915
Available-for-Sale More than One Year, Holding Period, Estimated Fair Value $ 22,781 $ 50,625
Available-for-Sale More than One Year, Holding Period, Number of Securities | Security 9 19
Available-for-Sale, Gross Unrealized Loss $ 1,380 $ 1,203
Available-for-Sale, Estimated Fair Value $ 117,689 $ 153,329
Available-for-Sale, Number of Securities | Security 41 40
U.S. government agency securities [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 394 $ 0
Available-for-Sale Within One Year, Estimated Fair Value $ 29,596 $ 5,000
Available-for-Sale Within One Year, Number of Securities | Security 11 1
Available-for-Sale More than One Year, Holding Period, Gross Unrealized Loss $ 918 $ 1,822
Available-for-Sale More than One Year, Holding Period, Estimated Fair Value $ 30,061 $ 73,142
Available-for-Sale More than One Year, Holding Period, Number of Securities | Security 10 26
Available-for-Sale, Gross Unrealized Loss $ 1,312 $ 1,822
Available-for-Sale, Estimated Fair Value $ 59,657 $ 78,142
Available-for-Sale, Number of Securities | Security 21 27
SBA loan pool securities [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 19 $ 155
Available-for-Sale Within One Year, Estimated Fair Value $ 13,971 $ 85,062
Available-for-Sale Within One Year, Number of Securities | Security 3 15
Available-for-Sale More than One Year, Holding Period, Gross Unrealized Loss $ 338 $ 433
Available-for-Sale More than One Year, Holding Period, Estimated Fair Value $ 11,362 $ 11,975
Available-for-Sale More than One Year, Holding Period, Number of Securities | Security 4 4
Available-for-Sale, Gross Unrealized Loss $ 357 $ 588
Available-for-Sale, Estimated Fair Value $ 25,333 $ 97,037
Available-for-Sale, Number of Securities | Security 7 19
Corporate bonds [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 17 $ 4
Available-for-Sale Within One Year, Estimated Fair Value $ 5,004 $ 5,021
Available-for-Sale Within One Year, Number of Securities | Security 1 1
Available-for-Sale More than One Year, Holding Period, Gross Unrealized Loss $ 27 $ 68
Available-for-Sale More than One Year, Holding Period, Estimated Fair Value $ 7,971 $ 7,925
Available-for-Sale More than One Year, Holding Period, Number of Securities | Security 2 2
Available-for-Sale, Gross Unrealized Loss $ 44 $ 72
Available-for-Sale, Estimated Fair Value $ 12,975 $ 12,946
Available-for-Sale, Number of Securities | Security 3 3
Other securities [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ 25 $ 0
Available-for-Sale Within One Year, Estimated Fair Value $ 21,861 $ 0
Available-for-Sale Within One Year, Number of Securities | Security 3 0
Available-for-Sale More than One Year, Holding Period, Gross Unrealized Loss $ 88 $ 80
Available-for-Sale More than One Year, Holding Period, Estimated Fair Value $ 937 $ 1,945
Available-for-Sale More than One Year, Holding Period, Number of Securities | Security 3 4
Available-for-Sale, Gross Unrealized Loss $ 113 $ 80
Available-for-Sale, Estimated Fair Value $ 22,798 $ 1,945
Available-for-Sale, Number of Securities | Security 6 4
Equity security [Member]    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss   $ 36
Available-for-Sale Within One Year, Estimated Fair Value   $ 214
Available-for-Sale Within One Year, Number of Securities | Security   1
Available-for-Sale More than One Year, Holding Period, Gross Unrealized Loss   $ 0
Available-for-Sale More than One Year, Holding Period, Estimated Fair Value   $ 0
Available-for-Sale More than One Year, Holding Period, Number of Securities | Security   0
Available-for-Sale, Gross Unrealized Loss   $ 36
Available-for-Sale, Estimated Fair Value   $ 214
Available-for-Sale, Number of Securities | Security   1