Derivative Financial Instruments (Schedule of Amounts Related to Interest Rate Derivatives Included in Income Designated as Hedges of Cash Flows) (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Junior Subordinated Deferred Interest Debentures [Member]
Amount of gain (loss) recognized in other comprehensive income	$ (1,716)	$ (3,089)	$ (1,651)	$ (5,566)
Amount reclassified from accumulated other comprehensive income to interest expense on junior subordinated deferrable interest debentures	1,100	1,084	2,186	2,195
Variable-Rate loans, Interest Rate Swaps/Caps/Floors [Member]
Amount of gain (loss) recognized in other comprehensive income		34,959		50,731
Amount reclassified from accumulated other comprehensive income to interest income on loans	$ 9,345	$ 11,033	$ 18,690	$ 21,970

Interest expense reclassified from accumulated other comprehensive income

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- Definition

Interest income reclassified from accumulated other comprehensive income

+ 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

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 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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