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Capital Ratios (Details) (USD $)	9 Months Ended
	Sep. 30, 2012	Dec. 31, 2011
Capital Ratios
Tier 1 Capital (to Average Assets), Actual Ratio (as a percent)	12.79%	12.74%
Tier 1 Capital (to Risk Weighted Assets), Actual Ratio (as a percent)	21.77%	22.73%
Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent)	22.93%	23.99%
Identified intangibles and goodwill	$ 291,419,000
Percentage of capital securities issued by trust qualifying as Tier I capital, maximum	25.00%
Capital securities issued by the trust, qualifying as Tier I capital	$ 190,726,000	$ 190,726,000

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Represents capital securities issued by trust that is qualified as Tier I capital as on the reporting date.

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The aggregate amount of identified intangible assets and goodwill recorded in connection with acquisitions made by the entity, are deducted from the sum of core capital elements while determining capital ratios of the entity.

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Represents the maximum percentage of capital securities issued by the trust qualifying as Tier I capital on an aggregate basis.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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