Derivative Instruments (Details 1) (Interest Rate Swap Member, Availableforsale Securities Member, USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Interest Rate Swap Member \| Availableforsale Securities Member
Net Derivatives Gains Losses Recognized On Fair Value Derivatives And Related Hedged Items
Derivative Instruments Gain Loss Recognized In Income Net	$ (489)	$ (877)	$ (266)	$ (1,200)
Change In Unrealized Gain Loss On Hedged Item In Fair Value Hedge	694	1,046	596	1,500
Gain Loss On Fair Value Hedge Ineffectiveness Net	$ 205	$ 169	$ 330	$ 300

Net Derivatives Gains (Losses) Recognized on Fair Value Derivatives and Related Hedged Items.

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- Definition

Amount of the increase or decrease in fair value during the period of the hedged item in a fair value hedge. Recognized in earnings and is offset by the gain (loss) on the hedging instrument to the extent that the fair value hedge is determined to be effective.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45
-Subparagraph a(1)

+ Details

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- Definition

The amount of net gains and losses recognized in income during the period on derivative instruments designated and qualifying as hedging instruments in fair value hedges and related hedged items designated and qualifying in fair value hedges, on derivative instruments designated and qualifying as hedging instruments in cash flow hedges, and on derivative instruments not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 205G

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44C
-Subparagraph b

+ Details

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- Definition

Net gain (loss) recognized in earnings during the reporting period representing the amount of the fair value of the hedges' ineffectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45
-Subparagraph a(1)

+ Details

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