Assets Measured at Fair Value on Recurring Basis (Detail) (USD $) | Sep. 30, 2013 | Dec. 31, 2012 |
In Thousands, unless otherwise specified |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | $242,957 | $621,507 |
Derivative Liability | 79 | ' |
Government sponsored residential mortgage-backed securities | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 104,311 | 328,023 |
U.S. government guaranteed mortgage-backed securities | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 73,710 | 130,735 |
Corporate bonds | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 26,650 | 52,337 |
State and municipal bonds | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 21,116 | 40,846 |
Government sponsored enterprise obligations | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 9,608 | 62,060 |
Mutual funds | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 5,945 | 6,046 |
Common and preferred stock | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 1,617 | 1,460 |
Interest Rate Swap | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Derivative Liability | 79 | ' |
Private label residential mortgage-backed securities | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | 52,337 |
Level 1 | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 7,562 | 7,506 |
Derivative Liability | ' | ' |
Level 1 | Government sponsored residential mortgage-backed securities | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 1 | U.S. government guaranteed mortgage-backed securities | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 1 | Corporate bonds | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 1 | State and municipal bonds | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 1 | Government sponsored enterprise obligations | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 1 | Mutual funds | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 5,945 | 6,046 |
Level 1 | Common and preferred stock | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 1,617 | 1,460 |
Level 1 | Interest Rate Swap | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Derivative Liability | ' | ' |
Level 1 | Private label residential mortgage-backed securities | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 2 | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 235,395 | 614,001 |
Derivative Liability | 79 | ' |
Level 2 | Government sponsored residential mortgage-backed securities | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 104,311 | 328,023 |
Level 2 | U.S. government guaranteed mortgage-backed securities | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 73,710 | 130,735 |
Level 2 | Corporate bonds | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 26,650 | ' |
Level 2 | State and municipal bonds | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 21,116 | 40,846 |
Level 2 | Government sponsored enterprise obligations | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | 9,608 | 62,060 |
Level 2 | Mutual funds | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 2 | Common and preferred stock | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 2 | Interest Rate Swap | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Derivative Liability | 79 | ' |
Level 2 | Private label residential mortgage-backed securities | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | 52,337 |
Level 3 | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Derivative Liability | ' | ' |
Level 3 | Government sponsored residential mortgage-backed securities | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 3 | U.S. government guaranteed mortgage-backed securities | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 3 | Corporate bonds | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 3 | State and municipal bonds | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 3 | Government sponsored enterprise obligations | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 3 | Mutual funds | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 3 | Common and preferred stock | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |
Level 3 | Interest Rate Swap | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Derivative Liability | ' | ' |
Level 3 | Private label residential mortgage-backed securities | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] | ' | ' |
Available-for-sale securities | ' | ' |