Derivative Instruments (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2011
Derivative Instruments
Notional amounts of swaps with customers	$ 570,268
Number of swaps with customers	169
Number of swaps with derivative counterparties	169
Notional amount of swaps with derivative counterparties	570,268
Fair value of derivatives, in a net liability position	30,123
Collateral posted	28,449
Cash collateral posted	0
Additional collateral required if in breach	$ 1,674

Cash collateral already posted aggregate fair value.

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- Definition

Notional amount of other derivatives not designated as hedging instruments of counterparties.

+ Details

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- Definition

Number of swaps.

+ Details

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- Definition

Number of swaps with counterparties.

+ Details

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- Definition

The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44D
-Subparagraph c

+ Details

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44D
-Subparagraph c

+ Details

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- Details

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain or loss on that instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44D
-Subparagraph b

+ Details

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- Definition

Aggregate notional amount of all derivatives not designated as a hedging instrument. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument.

+ Details

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