Off-Balance Sheet Credit Risk (Details) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Fair value of securities accepted as collateral permitted to sell or repledge	$ 927.4	$ 864.7
Fair value of collateral securities sold or repledged		109.6
Letters of credit outstanding	9.2	9.2
Loan Origination Commitments [Member]
Outstanding commitments to originate loans	253.7	107.2
Unused lines of Credit [Member]
Unused lines of credit to commercial and consumer borrowers	$ 98.5	$ 97.4

Fair value as of the balance sheet date of customer securities accepted as collateral by the entity that it is permitted by contract or custom to sell or re-pledge to counterparties as collateral.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

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