Fair Value Measurements (Beginning And Ending Balances Of Derivative Assets Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Thousands	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Fair Value Measurements
Balance, beginning of period	$ 1,090	$ 945
Transfers to Level 3	457
Cash settlements	(1,393)	(348)
Realized gains (losses) included in other non-interest income	515	1,097
Realized gains (losses) included in other non-interest expense	49	(112)
Balance, end of period	$ 718	$ 1,582

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain Included in Earnings

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- Definition

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, (Loss) Included in Earnings

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Details

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- Definition

This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to assets measured at fair value on a recurring basis using unobservable inputs (Level 3).

+ References

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesSalesIssuancesSettlements
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Transfers into assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

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