Derivative And Hedging Activities (Details 3) (USD $)	9 Months Ended	12 Months Ended	9 Months Ended
Sep. 30, 2011 Interest rate-related instruments - customer and mirror [Member] Capital market fees [Member]	Sep. 30, 2010 Interest rate-related instruments - customer and mirror [Member] Capital market fees [Member]	Dec. 31, 2010 Capital market fees [Member]	Sep. 30, 2011 Foreign currency exchange forwards [Member] Capital market fees [Member]	Sep. 30, 2010 Foreign currency exchange forwards [Member] Capital market fees [Member]	Sep. 30, 2011 Interest rate lock commitments (mortgage) [Member]	Sep. 30, 2010 Interest rate lock commitments (mortgage) [Member]	Sep. 30, 2011 Forward commitments (mortgage) [Member]	Sep. 30, 2010 Forward commitments (mortgage) [Member]
Gain (loss) on derivative instruments not designated as hedging instruments
Gain / (Loss) Recognized in Income	$ (3,379,000)	$ (4,420,000)	$ (1,900,000)	$ 345,000	$ 531,000	$ 10,935,000	$ 8,516,000	$ (11,386,000)	$ (4,782,000)

Net gain (loss) from the increase (decrease) in fair value of derivative instrument not designated as hedging instrument.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(1)(b)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624171-113959

Name:	us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration