Derivative Instruments (Narrative) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2011
Derivative Instruments
Notional amount of fair value derivatives	$ 15.1
Notional amount of other derivative instruments	516.4
Aggregate fair value of interest rate swap in net liability position	16.9
Collateral posted for interest rate swaps in a net liability position as of the end of the reporting period	16.9
Manufacturing group notional amount percent	24.30%
Derivative loss from industry concentration	$ 2.8

Manufacturing group notional amount percent

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- Definition

Aggregate notional amount of interest rate swap derivatives not designated as a hedging instrument.

+ Details

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- Definition

The aggregate fair value amounts of interest rate swaps in a net liability position at the end of the reporting period.

+ Details

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- Definition

The aggregate value of collateral posted for interest rate swaps in a net liability position as of the end of the reporting period.

+ Details

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- Details

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 9, 10, 11, 12

+ Details

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- Definition

Aggregate notional amount of all derivatives designated as a fair value 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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