| **Investment Securities (Details) (USD $)In Thousands, unless otherwise specified** | Mar. 31, 2014 | Dec. 31, 2013 |
|-------------------------------------------------------------------------------------|---------------|---------------|
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | $ 420,619     | $ 438,057     | [1] |
| Gross unrealized gains                                                              | 2,921         | 3,048         |  |
| Gross unrealized losses                                                             | 21,072        | 26,491        |  |
| Estimated fair value                                                                | 402,468       | 414,614       | [1] |
| **Held-to-maturity Securities [Abstract]**                                          |          |          |  |
| Amortized cost                                                                      | 149,060       | 151,795       |  |
| Gross unrealized gains                                                              | 0             | 0             |  |
| Gross unrealized losses                                                             | 8,058         | 10,670        |  |
| Estimated fair value                                                                | 141,002       | 141,125       | [1] |
| Amortized cost, Total                                                               | 569,679       | 589,852       |  |
| Gross unrealized gains, Total                                                       | 2,921         | 3,048         |  |
| Gross unrealized losses, Total                                                      | 29,130        | 37,161        |  |
| Estimated fair value, Total                                                         | 543,470       | 555,739       |  |
| Obligations of U.S. government sponsored enterprises [Member]                       |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 2,045         | 2,051         |  |
| Gross unrealized gains                                                              | 25            | 26            |  |
| Gross unrealized losses                                                             | 0             | 0             |  |
| Estimated fair value                                                                | 2,070         | 2,077         |  |
| Residential mortgage-backed securities - GSE [Member]                               |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 356,022       | 364,513       |  |
| Gross unrealized gains                                                              | 971           | 974           |  |
| Gross unrealized losses                                                             | 19,429        | 24,340        |  |
| Estimated fair value                                                                | 337,564       | 341,147       |  |
| **Held-to-maturity Securities [Abstract]**                                          |          |          |  |
| Amortized cost                                                                      | 138,991       | 141,724       |  |
| Gross unrealized gains                                                              | 0             | 0             |  |
| Gross unrealized losses                                                             | 7,564         | 9,907         |  |
| Estimated fair value                                                                | 131,427       | 131,817       |  |
| Residential mortgage-backed securities - Private [Member]                           |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 19,338        | 19,770        |  |
| Gross unrealized gains                                                              | 953           | 982           |  |
| Gross unrealized losses                                                             | 9             | 0             |  |
| Estimated fair value                                                                | 20,282        | 20,752        |  |
| Commercial mortgage-backed securities - GSE [Member]                                |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 22,670        | 22,767        |  |
| Gross unrealized gains                                                              | 0             | 0             |  |
| Gross unrealized losses                                                             | 1,080         | 1,328         |  |
| Estimated fair value                                                                | 21,590        | 21,439        |  |
| Commercial mortgage-backed securities - Private [Member]                            |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 10,398        | 10,408        |  |
| Gross unrealized gains                                                              | 0             | 0             |  |
| Gross unrealized losses                                                             | 554           | 823           |  |
| Estimated fair value                                                                | 9,844         | 9,585         |  |
| **Held-to-maturity Securities [Abstract]**                                          |          |          |  |
| Amortized cost                                                                      | 10,069        | 10,071        |  |
| Gross unrealized gains                                                              | 0             | 0             |  |
| Gross unrealized losses                                                             | 494           | 763           |  |
| Estimated fair value                                                                | 9,575         | 9,308         |  |
| Business Development Company investment [Member]                                    |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 1,753         | 1,753         |  |
| Gross unrealized gains                                                              | 898           | 984           |  |
| Gross unrealized losses                                                             | 0             |          |  |
| Estimated fair value                                                                | 2,651         | 2,737         |  |
| Corporate notes [Member]                                                            |          |          |  |
| **Available-for-sale Securities [Abstract]**                                        |          |          |  |
| Amortized cost                                                                      | 8,393         | 16,795        |  |
| Gross unrealized gains                                                              | 74            | 82            |  |
| Gross unrealized losses                                                             | 0             | 0             |  |
| Estimated fair value                                                                | $ 8,467       | $ 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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