Covered Assets and FDIC Loss-sharing Asset (Narrative) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Percentage of loss assumed by FDIC on sale of covered OREO	80.00%
Percentage of loss assumed by FDIC on sale of covered OREO if minimum loss share is met		95.00%
Percentage of loss recovery agreement	80.00%	95.00%
Percentage of Clawback	50.00%
Percentage of stated threshold	20.00%
Percentage of assets premium	25.00%
Amount of estimated clawback liability	$ 3.3
Provision expense on covered loans	2.3
Impairment expenses	3.5
Negative provision to adjust allowance for loss	1.2
Federal deposit insurance corporation loss-sharing indemnified assets	186.5
Federal deposit insurance corporation loss-sharing indemnified assets receivable	$ 7.4
Maximum [Member]
Loss sharing agreement effective years	10
Loss recovery provision effective years	10
Percentage of cumulative loss-sharing	25.00%
Minimum [Member]
Loss sharing agreement effective years	5
Loss recovery provision effective years	8
Percentage of cumulative loss-sharing	20.00%

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- Definition

Federal deposit insurance corporation loss-sharing indemnified assets

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Federal deposit insurance corporation loss-sharing indemnified assets receivable

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Loss recovery provision effective years

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Loss sharing agreement in years

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Negative provision to adjust allowance for loss

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Percentage of assets premium

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Percentage of Clawback

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Percentage of cumulative loss-sharing

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- Definition

Percentage of Loss Assumed by Federal Deposit Insurance Corporation on Sale of Covered Other Real Estate Owned

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Percentage of Loss Assumed by Federal Deposit Insurance Corporation on Sale of Covered Other Real Estate Owned if Minimum Loss Share is Met

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Percentage of loss recovery agreement

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Percentage of stated threshold

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Provision Expense On Covered Loans

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- Definition

The charge against earnings resulting from the aggregate write down of all assets from their carrying value to their fair value.

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