Investment Securities (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012 Security	Jun. 30, 2011	Jun. 30, 2012 Security	Jun. 30, 2011	May 09, 2012	Dec. 31, 2011 Security
Investment Securities (Textual) [Abstract]
Number of available for sale investment securities in the less than twelve month category	8		8			10
Number of available for sale investment securities in the twelve month or more category	7		7			6
Reclassification of held-to-maturity investment portfolio to available for sale					$ 269,000
Increased total shareholders' equity by reclassification			5,300
Interest only strip security	2,632		2,632			2,894
Pledged investment securities	106,618		106,618			311,442
Proceeds from sale of available-for-sale investment securities	257,645	0	306,610	0
Net gains	8,797	0	9,006	0
Aggregate amortized cost of private - label securities	701		701			765
Aggregate fair value of private - label securities	$ 635		$ 635			$ 662

Interest only strip security.

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Number of available for sale investment securities in the less than twelve month category.

+ References

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Number of available for sale investment securities in the twelve month or more category.

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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.

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This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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- Definition

For any transfer of securities categorized as held-to-maturity, this item represents the net carrying amount of the transferred security to another category of investments in debt and equity securities (trading or available-for-sale).

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This element represents the fair value of assets categorized as other which are not in and of themselves material enough to require separate disclosure.

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Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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The increase (decrease) in stockholders' equity during the period.

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