| **Investment Securities (Details) (USD $)In Thousands, unless otherwise specified** | Jun. 30, 2014 | Dec. 31, 2013 |
|-------------------------------------------------------------------------------------|---------------|---------------|
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | $ 409,715     | $ 438,057     | [1] |
| Gross unrealized gains                                                              | 2,456         | 3,048         |  |
| Gross unrealized losses                                                             | 13,061        | 26,491        |  |
| Estimated fair value                                                                | 399,110       | 414,614       | [1] |
| **Held-to-maturity Securities [Abstract]**                                          |          |          |  |
| Amortized cost                                                                      | 147,055       | 151,795       |  |
| Gross unrealized gains                                                              | 0             | 0             |  |
| Gross unrealized losses                                                             | 4,767         | 10,670        |  |
| Estimated fair value                                                                | 142,288       | 141,125       | [1] |
| Amortized cost, Total                                                               | 556,770       | 589,852       |  |
| Gross unrealized gains, Total                                                       | 2,456         | 3,048         |  |
| Gross unrealized losses, Total                                                      | 17,828        | 37,161        |  |
| Estimated fair value, Total                                                         | 541,398       | 555,739       |  |
| Obligations of U.S. government sponsored enterprises [Member]                       |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 2,040         | 2,051         |  |
| Gross unrealized gains                                                              | 24            | 26            |  |
| Gross unrealized losses                                                             | 0             | 0             |  |
| Estimated fair value                                                                | 2,064         | 2,077         |  |
| Residential mortgage-backed securities - GSE [Member]                               |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 347,916       | 364,513       |  |
| Gross unrealized gains                                                              | 1,278         | 974           |  |
| Gross unrealized losses                                                             | 12,298        | 24,340        |  |
| Estimated fair value                                                                | 336,896       | 341,147       |  |
| **Held-to-maturity Securities [Abstract]**                                          |          |          |  |
| Amortized cost                                                                      | 136,987       | 141,724       |  |
| Gross unrealized gains                                                              | 0             | 0             |  |
| Gross unrealized losses                                                             | 4,589         | 9,907         |  |
| Estimated fair value                                                                | 132,398       | 131,817       |  |
| Residential mortgage-backed securities - Private [Member]                           |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 18,404        | 19,770        |  |
| Gross unrealized gains                                                              | 1,104         | 982           |  |
| Gross unrealized losses                                                             | 0             | 0             |  |
| Estimated fair value                                                                | 19,508        | 20,752        |  |
| Commercial mortgage-backed securities - GSE [Member]                                |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 22,573        | 22,767        |  |
| Gross unrealized gains                                                              | 0             | 0             |  |
| Gross unrealized losses                                                             | 522           | 1,328         |  |
| Estimated fair value                                                                | 22,051        | 21,439        |  |
| Commercial mortgage-backed securities - Private [Member]                            |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 10,387        | 10,408        |  |
| Gross unrealized gains                                                              | 0             | 0             |  |
| Gross unrealized losses                                                             | 241           | 823           |  |
| Estimated fair value                                                                | 10,146        | 9,585         |  |
| **Held-to-maturity Securities [Abstract]**                                          |          |          |  |
| Amortized cost                                                                      | 10,068        | 10,071        |  |
| Gross unrealized gains                                                              | 0             | 0             |  |
| Gross unrealized losses                                                             | 178           | 763           |  |
| Estimated fair value                                                                | 9,890         | 9,308         |  |
| Business Development Company investment [Member]                                    |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 0             | 1,753         |  |
| Gross unrealized gains                                                              | 0             | 984           |  |
| Gross unrealized losses                                                             | 0             |          |  |
| Estimated fair value                                                                | 0             | 2,737         |  |
| Corporate notes [Member]                                                            |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 8,395         | 16,795        |  |
| Gross unrealized gains                                                              | 50            | 82            |  |
| Gross unrealized losses                                                             | 0             | 0             |  |
| Estimated fair value                                                                | $ 8,445       | $ 16,877      |  |
|                                                                                     |
| [1]Derived from audited consolidated financial statements                           |

| X                                                                                                                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Available-for-sale and Held-to-maturity Securities, Amortized Cost Basis
+ References
No definition available.
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| - Definition
Available-for-sale and Held-to-maturity Securities, Gross Unrealized Gains
+ References
No definition available.
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| - Definition
Available-for-sale and Held-to-maturity Securities, Gross Unrealized Losses
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                 |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Held-to-maturity Securities, Unrecognized Holding Gain
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682
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| X                                                                                                                                                                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of debt and equity financial instruments classified as either held-to-maturity or available-for-sale.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value of investments in debt securities classified as held-to-maturity.
+ References
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