v2.4.0.6
Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)
In Thousands, unless otherwise specified
Jun. 30, 2012
Dec. 31, 2011
Assets  
Investment securities available-for-sale$ 321,322$ 322,512
Derivatives1,5961,349
Total322,918323,861
Liabilities  
Derivatives1,5961,349
Total1,5961,349
US Treasury and Government
  
Assets  
Investment securities available-for-sale136,155169,460
Residential Mortgage Backed Securities
  
Assets  
Investment securities available-for-sale184,107151,992
Corporate Securities
  
Assets  
Investment securities available-for-sale1,0601,060
Quoted Prices in Active Markets for Identical Assets (Level 1)
  
Assets  
Derivatives00
Total00
Liabilities  
Derivatives00
Total0 
Quoted Prices in Active Markets for Identical Assets (Level 1) | US Treasury and Government
  
Assets  
Investment securities available-for-sale00
Quoted Prices in Active Markets for Identical Assets (Level 1) | Residential Mortgage Backed Securities
  
Assets  
Investment securities available-for-sale00
Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate Securities
  
Assets  
Investment securities available-for-sale00
Significant Other Observable Inputs (Level 2)
  
Assets  
Derivatives1,5961,349
Total321,858322,801
Liabilities  
Derivatives1,5961,349
Total1,5961,349
Significant Other Observable Inputs (Level 2) | US Treasury and Government
  
Assets  
Investment securities available-for-sale136,155169,460
Significant Other Observable Inputs (Level 2) | Residential Mortgage Backed Securities
  
Assets  
Investment securities available-for-sale184,107151,992
Significant Other Observable Inputs (Level 2) | Corporate Securities
  
Assets  
Investment securities available-for-sale00
Significant Unobservable Inputs (Level 3)
  
Assets  
Derivatives00
Total1,0601,060
Liabilities  
Derivatives00
Total00
Significant Unobservable Inputs (Level 3) | US Treasury and Government
  
Assets  
Investment securities available-for-sale00
Significant Unobservable Inputs (Level 3) | Residential Mortgage Backed Securities
  
Assets  
Investment securities available-for-sale00
Significant Unobservable Inputs (Level 3) | Corporate Securities
  
Assets  
Investment securities available-for-sale$ 1,060$ 1,060