| **Investment Securities (Maturity Schedule) (Details) - USD ($) $ in Thousands**               | Sep. 30, 2015 | Dec. 31, 2014 |
|------------------------------------------------------------------------------------------------|---------------|---------------|
| **Amortized Cost**                                                                             |          |          |  |
| Total                                                                                          | $ 379,125     |          |  |
| **Estimated Fair Value**                                                                       |          |          |  |
| Total                                                                                          | 375,929       | $ 350,040     | [1] |
| **Amortized Cost**                                                                             |          |          |  |
| Total                                                                                          | 152,670       | 142,461       | [1] |
| **Estimated Fair Value**                                                                       |          |          |  |
| Total                                                                                          | 151,935       | 140,875       | [1] |
| US Government-sponsored Enterprises Debt Securities [Member]                                   |          |          |  |
| **Amortized Cost**                                                                             |          |          |  |
| Due after one year through five years, amortized cost                                          | 2,011         |          |  |
| **Estimated Fair Value**                                                                       |          |          |  |
| Due after one year through five years, estimated fair value                                    | 2,019         |          |  |
| Total                                                                                          | 2,019         | 2,044         |  |
| Residential Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |          |          |  |
| **Amortized Cost**                                                                             |          |          |  |
| Due after five years through 10 years                                                          | 1,930         |          |  |
| Due after ten years                                                                            | 290,025       |          |  |
| **Estimated Fair Value**                                                                       |          |          |  |
| Due after five years through 10 years                                                          | 1,984         |          |  |
| Due after ten years                                                                            | 286,157       |          |  |
| Total                                                                                          | 288,141       | 290,145       |  |
| **Amortized Cost**                                                                             |          |          |  |
| Due after ten years                                                                            | 123,735       |          |  |
| **Estimated Fair Value**                                                                       |          |          |  |
| Due after ten years                                                                            | 123,182       |          |  |
| Total                                                                                          | 123,182       | 130,877       |  |
| Residential Mortgage-backed Securities, Issued by Private Enterprises [Member]                 |          |          |  |
| **Amortized Cost**                                                                             |          |          |  |
| Due after ten years                                                                            | 14,456        |          |  |
| **Estimated Fair Value**                                                                       |          |          |  |
| Due after ten years                                                                            | 15,083        |          |  |
| Total                                                                                          | 15,083        | 17,271        |  |
| **Amortized Cost**                                                                             |          |          |  |
| Due after ten years                                                                            | 18,875        |          |  |
| **Estimated Fair Value**                                                                       |          |          |  |
| Due after ten years                                                                            | 18,621        |          |  |
| Total                                                                                          | 18,620        |          |  |
| Commercial mortgage-backed securities - GSE [Member]                                           |          |          |  |
| **Amortized Cost**                                                                             |          |          |  |
| Due after five years through 10 years                                                          | 22,080        |          |  |
| **Estimated Fair Value**                                                                       |          |          |  |
| Due after five years through 10 years                                                          | 22,148        |          |  |
| Total                                                                                          | 22,148        | 21,958        |  |
| Commercial Mortgage-backed Securities, Issued by Private Enterprises [Member]                  |          |          |  |
| **Amortized Cost**                                                                             |          |          |  |
| Due after ten years                                                                            | 17,879        |          |  |
| **Estimated Fair Value**                                                                       |          |          |  |
| Due after ten years                                                                            | 17,813        |          |  |
| Total                                                                                          | 17,813        | 10,215        |  |
| **Amortized Cost**                                                                             |          |          |  |
| Due after ten years                                                                            | 10,060        |          |  |
| **Estimated Fair Value**                                                                       |          |          |  |
| Due after ten years                                                                            | 10,132        |          |  |
| Total                                                                                          | 10,133        | 9,998         |  |
| Corporate notes [Member]                                                                       |          |          |  |
| **Amortized Cost**                                                                             |          |          |  |
| Due after one year through five years, amortized cost                                          | 30,744        |          |  |
| **Estimated Fair Value**                                                                       |          |          |  |
| Due after one year through five years, estimated fair value                                    | 30,725        |          |  |
| Total                                                                                          | $ 30,725      | $ 8,407       |  |
|                                                                                                |
| [1]Derived from audited consolidated financial statements                                      |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This item represents the cost of debt 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.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after adjustments of available-for-sale debt securities at cost, maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value of available-for-sale debt securities maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after adjustments of available-for-sale debt securities at cost, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
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| - Definition
Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
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| - Definition
Amount after adjustments of available-for-sale debt securities at cost, maturing after the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
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| - Definition
Fair value of available-for-sale debt securities maturing after the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
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| - Definition
Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.
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| - Definition
Fair value of held-to-maturity debt securities maturing after the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
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| - Definition
Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing after the tenth fiscal year following the latest fiscal year.
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Fair value of investments in debt securities classified as held-to-maturity.
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