| **Impairment of Investment Securities (Tables)**                                                                     | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
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| **Impairment of Investment Securities Disclosure [Abstract]**                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| Schedule of Unrealized Losses and Estimated Fair Values                                                              | The following table presents the gross unrealized losses and estimated fair values at December 31, 2013 by investment category and time frame for which the securities have been in a continuous unrealized loss position: Less Than 12 Months 12 Months or More Total EstimatedFair Value GrossUnrealizedLosses EstimatedFair Value GrossUnrealizedLosses EstimatedFair Value GrossUnrealizedLosses (dollars in thousands)Obligations of U.S. Government Agencies:           Mortgage-Backed Securities – Residential$2,035 $(59) $— $— $2,035 $(59)Obligations of U.S. Government-Sponsored Enterprises:           Mortgage-Backed Securities – Residential632,231 (22,844) 65,324 (4,319) 697,555 (27,163)Other Government-Sponsored Enterprises183,542 (1,448) 24,501 (479) 208,043 (1,927)Pooled Trust Preferred Collateralized Debt Obligations2,401 (237) 21,122 (18,280) 23,523 (18,517)Total Securities Available for Sale$820,209 $(24,588) $110,947 $(23,078) $931,156 $(47,666) At December 31, 2013, pooled trust preferred collateralized debt obligations accounted for 39% of unrealized losses, while fixed income securities issued by U.S. Government-sponsored enterprises comprised 61% of total unrealized losses.The following table presents the gross unrealized losses and estimated fair value at December 31, 2012 for available-for-sale and securities by investment category and time frame for which the securities had been in a continuous unrealized loss position:  Less Than 12 Months 12 Months or More Total EstimatedFair Value GrossUnrealizedLosses EstimatedFair Value GrossUnrealizedLosses EstimatedFair Value GrossUnrealizedLosses (dollars in thousands)Obligations of U.S. Government Agencies:           Mortgage-Backed Securities – Residential$— $— $13 $—(a) $13 $—Obligations of U.S. Government-Sponsored Enterprises:           Mortgage-Backed Securities – Residential76,296 (392) 21 —(a)76,317 (392)Other Government-Sponsored Enterprises59,303 (72) — —  59,303 (72)Pooled Trust Preferred Collateralized Debt Obligations— — 23,316 (28,496) 23,316 (28,496)Total Securities Available for Sale$135,599 $(464) $23,350 $(28,496) $158,949 $(28,960)(a)Gross unrealized losses related to these types of securities are less than $1 thousand. |
| Pooled Trust Preferred Collateralized Debt Obligations                                                               | The following table provides additional information related to our pooled trust preferred collateralized debt obligations as of December 31, 2013:DealClass BookValue Estimated FairValue UnrealizedGain(Loss) Moody’s/FitchRatings NumberofBanks DeferralsandDefaultsas a % ofCurrentCollateral ExcessSubordinationas a % ofCurrentPerformingCollateral(dollars in thousands)Pre TSL IVMezzanine $1,830 $1,264 $(566) B1/B 6 18.05% 58.54%Pre TSL VMezzanine 57 34 (23) C/- 3 100.00 0.00Pre TSL VIIMezzanine 2,581 2,367 (214) Ca/C 14 54.14 0.00Pre TSL VIIIMezzanine 1,956 1,100 (856) C/C 30 58.01 0.00Pre TSL IXMezzanine 2,304 1,173 (1,131) Caa1/C 42 30.29 3.36Pre TSL XMezzanine 1,388 1,291 (97) Caa3/C 46 35.07 0.00Pre TSL XIIMezzanine 5,374 2,852 (2,522) Caa3/C 68 30.26 0.00Pre TSL XIIIMezzanine 12,452 6,862 (5,590) Caa3/C 61 31.09 16.78Pre TSL XIVMezzanine 13,653 6,234 (7,419) Ca/C 59 37.00 42.17MMCap IMezzanine 445 346 (99) Ca/C 11 58.76 10.41Total  $42,040 $23,523 $(18,517)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| Cumulative Roll Forward of Credit Losses Recognized in Earnings for Debt Securities Held and Not Intended to be Sold | The table below provides a cumulative roll forward of credit losses recognized in earnings for debt securities held and not intended to be sold for the years ended December 31: 2013 2012 2011 (dollars in thousands)Balance, beginning (a)$43,274 $44,736 $44,850Credit losses on debt securities for which other-than-temporary impairment was not previously recognized— — —Additional credit losses on debt securities for which other-than-temporary impairment was previously recognized— — —Increases in cash flows expected to be collected, recognized over the remaining life of the security (b)(2,375) (1,462) (114)Reduction for debt securities called during the period(13,356) — —Balance, ending$27,543 $43,274 $44,736(a)The beginning balance represents credit related losses included in other-than-temporary impairment charges recognized on debt securities in prior periods.(b)Represents the increase in cash flows recognized either as principal payments or interest income during the period.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |

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| - Definition
Pooled Trust Preferred Collateralized Debt Obligations [Table Text Block]
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No definition available.
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Tabular disclosure of the amount of other than temporary impairment (OTTI) related to credit losses recognized in earnings including: (a) the beginning balance of the amount related to credit losses on debt securities held by the investor at the beginning of the period for which a portion of an OTTI was recognized in other comprehensive income; (b) additions for the amount related to the credit loss for which an OTTI was not previously recognized; (c) reductions for securities sold during the period (realized); (d) reductions for securities for which the amount previously recognized in other comprehensive income was recognized in earnings because the investor intends to sell the security or more likely than not will be required to sell the security before recovery of its amortized cost basis; (e) additional increases to the amount related to the credit loss for which an OTTI was previously recognized when the investor does not intend to sell the security and it is not more likely than not that the investor will be required to sell the security before recovery of its amortized cost basis; (f) reductions for increases in cash flows expected to be collected that are recognized over the remaining life of the security; and (g) the ending balance of the amount related to credit losses on debt securities held by the entity at the end of the period for which a portion of an OTTI was recognized in other comprehensive income.
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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27340-111563Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 18B -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.
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For all investments in an unrealized loss position, including those for which other-than-temporary impairments have not been recognized in earnings (including investments for which a portion of an other-than-temporary impairment has been recognized in other comprehensive income), a tabular disclosure of the aggregate related fair value of investments with unrealized losses and the aggregate amount of unrealized losses (that is, the amount by which amortized cost basis exceeds fair value).
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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27290-111563
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