Amount of book value of the pooled issues.

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Amount of pooled issues that remained above investment grade.

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Available for sale securities book value.

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Available-for-sale, securities in unrealized loss, percentage.

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Estimate of future cash flows prepayment percentage in year three.

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Estimate of future cash flows prepayment percentage thereafter.

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Estimate of future cash flows prepayment percentage year four.

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Excess present value of future cash flows over our current book value.

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Excess subordination as a percentage of current performing collateral.

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Gross unrealized losses related to available for sale securities.

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Non-credit related losses on securities

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Number of banks and other financial institutions comprising the security.

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Number of pooled securities representing senior tranches.

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Percentage of principal amount in pooled security securities.

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Probabilities for performing collateral range.

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Probability of default.

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Probability percentage assigned to default bank.

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Probability percentage assigned to default bank subject to market indicators.

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Projected recovery rate.

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Subordinated tranches range.

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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 item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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The net amount of gross unrealized gains (losses) for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

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Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Impairment of Investment Securities (Details Textual) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2012 Bank	Jun. 30, 2011	Jun. 30, 2012 Securities Bank	Jun. 30, 2011	Dec. 31, 2011
Impairment of Investment Securities (Textual) [Abstract]
Corporate/Mortgage-Backed Securities, Amortized cost	$ 1,155,383,000		$ 1,155,383,000		$ 1,140,212,000
Corporate/Mortgage-Backed Securities, Estimated fair value	1,159,202,000		1,159,202,000		1,142,776,000
Available for sale securities book value	0		0
Number of banks and other financial institutions comprising the security	348		348
Unrealized loss position	57,122,000		57,122,000		84,710,000
Excess recognized as an adjustment to yield	(271,000)	0	(506,000)	0
Impairment of investment securities (Additional Textual) [Abstract]
Gross unrealized losses related to available for sale securities			less than $1 thousand		less than $1 thousand
Other-than-temporary impairment charges			0	0
Collateral issued by financial institutions	15,000,000,000		15,000,000,000
Number of pooled securities representing senior tranches			2
Amount of pooled issues that remained above investment grade	3,500,000		3,500,000
Amount of book value of the pooled issues	52,900,000		52,900,000
Estimate of future cash flows prepayment percentage in year three			20.00%
Estimate of future cash flows prepayment percentage year four			20.00%
Estimate of future cash flows prepayment percentage thereafter			2.00%
Probability percentage assigned to default bank			100.00%
Probability of default			100.00%
Projected recovery rate			0.00%
Probability percentage assigned to default bank subject to market indicators			10.00%
Equity Securities [Member]
Impairment of Investment Securities (Textual) [Abstract]
Total unrealized losses	0.00%		0.00%
Corporate/Mortgage-Backed Securities, Amortized cost	1,860,000		1,860,000		1,860,000
Corporate/Mortgage-Backed Securities, Estimated fair value	1,860,000		1,860,000		1,860,000
Trust Preferred Collateralized Debt Obligations [Member]
Impairment of Investment Securities (Textual) [Abstract]
Total unrealized losses	0.00%		0.00%
Corporate/Mortgage-Backed Securities, Estimated fair value	21,800,000		21,800,000
Available for sale securities book value	52,900,000		52,900,000
Non-credit related losses on securities			200,000	2,300,000
Obligations of U.S. Government-Sponsored Enterprises [Member]
Impairment of Investment Securities (Textual) [Abstract]
Total unrealized losses	0.00%		0.00%
Corporate/Mortgage-Backed Securities, Amortized cost	816,200,000		816,200,000
Corporate/Mortgage-Backed Securities, Estimated fair value	845,900,000		845,900,000
Obligations of U.S. Government Agencies [Member]
Impairment of Investment Securities (Textual) [Abstract]
Total unrealized losses	0.00%		0.00%
Corporate/Mortgage-Backed Securities, Amortized cost	30,500,000		30,500,000
Corporate/Mortgage-Backed Securities, Estimated fair value	34,600,000		34,600,000
Corporate Securities [Member]
Impairment of Investment Securities (Textual) [Abstract]
Corporate/Mortgage-Backed Securities, Amortized cost	11,800,000		11,800,000		11,800,000
Corporate/Mortgage-Backed Securities, Estimated fair value	12,000,000		12,000,000		11,400,000
Gross unrealized loss	71,000		71,000		600,000
Mortgage Backed Securities [Member]
Impairment of Investment Securities (Textual) [Abstract]
Corporate/Mortgage-Backed Securities, Amortized cost	846,698,000		846,698,000
Corporate/Mortgage-Backed Securities, Estimated fair value	880,536,000		880,536,000
Maximum [Member]
Impairment of Investment Securities (Textual) [Abstract]
Subordinated tranches range	35.00%		35.00%
Excess subordination as a percentage of current performing collateral			282.00%
Probabilities for performing collateral range			75.00%
Excess present value of future cash flows over our current book value			520.00%
Excess recognized as an adjustment to yield			500,000
Maximum [Member] \| Mortgage Backed Securities - Residential [Member]
Impairment of Investment Securities (Textual) [Abstract]
Gross unrealized loss	0		0		1,000
Maximum [Member] \| Corporate Fixed Income [Member]
Impairment of Investment Securities (Textual) [Abstract]
Total unrealized losses	0.00%		0.00%
Minimum [Member]
Impairment of Investment Securities (Textual) [Abstract]
Subordinated tranches range	7.00%		7.00%
Total principal amount of the respective securities	5.00%		5.00%
Excess subordination as a percentage of current performing collateral			8.00%
Probabilities for performing collateral range			0.33%
Excess present value of future cash flows over our current book value			29.00%
Excess recognized as an adjustment to yield	$ 300,000