Derivatives And Fair Value Measurements (Gains (Losses) On Derivatives In Cash Flow Hedging) (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Derivatives And Fair Value Measurements
Amount of gain (loss) on unrealized FSIRS recognized in other comprehensive income on derivative (effective portion)	$ (3,816)	$ (20,272)	$ (3,145)	$ (21,259)	$ 11,359	$ (21,259)
Amount of loss on realized FSIRS recognized in other comprehensive income on derivative					(11,691)
Amount of gain (loss) on realized FSIRS recognized in other comprehensive income on derivative	$ (3,816)	$ (20,272)	$ (3,145)	$ (21,259)	$ (332)	$ (21,259)

Derivative Instruments and Hedging Activities Disclosure [Abstract]

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ 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
-Clause 2

+ Details

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- Definition

The effective portion of gains on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

+ Details

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- Definition

The effective portion of losses on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

+ Details

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