Quarterly report pursuant to Section 13 or 15(d)

Investment Securities - Continuous Unrealized Loss Position (Detail)

v2.4.0.8
Investment Securities - Continuous Unrealized Loss Position (Detail) (USD $)
In Thousands, unless otherwise specified
Jun. 30, 2013
Security
Dec. 31, 2012
Security
Summary of Investment Holdings [Line Items]    
Available for Sale Within One Year, Gross Unrealized Loss $ 4,301 $ 638
Available for Sale Within One Year, Estimated Fair Value 221,108 85,291
Available for Sale Within One Year, Number of Securities 82 33
Available for Sale More than One Year, Gross Unrealized Loss 254 301
Available for Sale More than One Year, Estimated Fair Value 12,181 13,655
Available for Sale More than One Year, Number of Securities 5 7
Available for Sale, Gross Unrealized Loss 4,555 939
Available for Sale, Estimated Fair Value 233,289 98,946
Available for Sale, Number of Securities 87 40
Mortgage-backed securities [Member]
    
Summary of Investment Holdings [Line Items]    
Available for Sale Within One Year, Gross Unrealized Loss 1,871 186
Available for Sale Within One Year, Estimated Fair Value 79,024 28,354
Available for Sale Within One Year, Number of Securities 26 10
Available for Sale More than One Year, Gross Unrealized Loss      
Available for Sale More than One Year, Estimated Fair Value      
Available for Sale More than One Year, Number of Securities      
Available for Sale, Gross Unrealized Loss 1,871 186
Available for Sale, Estimated Fair Value 79,024 28,354
Available for Sale, Number of Securities 26 10
Collateralized Mortgage Obligations [Member]
    
Summary of Investment Holdings [Line Items]    
Available for Sale Within One Year, Gross Unrealized Loss 521 109
Available for Sale Within One Year, Estimated Fair Value 25,134 14,344
Available for Sale Within One Year, Number of Securities 10 5
Available for Sale More than One Year, Gross Unrealized Loss      
Available for Sale More than One Year, Estimated Fair Value      
Available for Sale More than One Year, Number of Securities      
Available for Sale, Gross Unrealized Loss 521 109
Available for Sale, Estimated Fair Value 25,134 14,344
Available for Sale, Number of Securities 10 5
U.S. government agency securities [Member]
    
Summary of Investment Holdings [Line Items]    
Available for Sale Within One Year, Gross Unrealized Loss 1,267 94
Available for Sale Within One Year, Estimated Fair Value 89,068 26,894
Available for Sale Within One Year, Number of Securities 31 9
Available for Sale More than One Year, Gross Unrealized Loss      
Available for Sale More than One Year, Estimated Fair Value      
Available for Sale More than One Year, Number of Securities      
Available for Sale, Gross Unrealized Loss 1,267 94
Available for Sale, Estimated Fair Value 89,068 26,894
Available for Sale, Number of Securities 31 9
Municipal bonds-taxable [Member]
    
Summary of Investment Holdings [Line Items]    
Available for Sale Within One Year, Gross Unrealized Loss 183 126
Available for Sale Within One Year, Estimated Fair Value 7,485 4,587
Available for Sale Within One Year, Number of Securities 6 4
Available for Sale More than One Year, Gross Unrealized Loss 3 9
Available for Sale More than One Year, Estimated Fair Value 444 1,964
Available for Sale More than One Year, Number of Securities 1 3
Available for Sale, Gross Unrealized Loss 186 135
Available for Sale, Estimated Fair Value 7,929 6,551
Available for Sale, Number of Securities 7 7
Corporate bonds [Member]
    
Summary of Investment Holdings [Line Items]    
Available for Sale Within One Year, Gross Unrealized Loss 108  
Available for Sale Within One Year, Estimated Fair Value 4,880   
Available for Sale Within One Year, Number of Securities 1   
Available for Sale More than One Year, Gross Unrealized Loss 168 246
Available for Sale More than One Year, Estimated Fair Value 10,819 10,738
Available for Sale More than One Year, Number of Securities 3 3
Available for Sale, Gross Unrealized Loss 276 246
Available for Sale, Estimated Fair Value 15,699 10,738
Available for Sale, Number of Securities 4 3
SBA Loan Pool Securities [Member]
    
Summary of Investment Holdings [Line Items]    
Available for Sale Within One Year, Gross Unrealized Loss 341 82
Available for Sale Within One Year, Estimated Fair Value 13,501 11,004
Available for Sale Within One Year, Number of Securities 4 3
Available for Sale More than One Year, Gross Unrealized Loss      
Available for Sale More than One Year, Estimated Fair Value      
Available for Sale More than One Year, Number of Securities      
Available for Sale, Gross Unrealized Loss 341 82
Available for Sale, Estimated Fair Value 13,501 11,004
Available for Sale, Number of Securities 4 3
Other securities [Member]
    
Summary of Investment Holdings [Line Items]    
Available for Sale Within One Year, Gross Unrealized Loss 10 1
Available for Sale Within One Year, Estimated Fair Value 2,016 12
Available for Sale Within One Year, Number of Securities 4 1
Available for Sale More than One Year, Gross Unrealized Loss 83 46
Available for Sale More than One Year, Estimated Fair Value 918 953
Available for Sale More than One Year, Number of Securities 1 1
Available for Sale, Gross Unrealized Loss 93 47
Available for Sale, Estimated Fair Value 2,934 965
Available for Sale, Number of Securities 5 2
Equity securities [Member]
    
Summary of Investment Holdings [Line Items]    
Available for Sale Within One Year, Gross Unrealized Loss   40
Available for Sale Within One Year, Estimated Fair Value   96
Available for Sale Within One Year, Number of Securities   1
Available for Sale More than One Year, Gross Unrealized Loss     
Available for Sale More than One Year, Estimated Fair Value     
Available for Sale More than One Year, Number of Securities     
Available for Sale, Gross Unrealized Loss   40
Available for Sale, Estimated Fair Value   $ 96
Available for Sale, Number of Securities   1