Derivatives and Hedging Activities (FV of Derivative Financial Instruments and Classification on Balance Sheet) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 28,061	$ 22,390
Liability Derivatives	201,540	225,824
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	28,535	22,688
Derivative Asset, Fair Value, Gross Asset	28,535	22,688
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	28,032	22,380
Liability Derivatives	33,402	27,950
Interest rate swaps [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Liability Derivatives	5,370	5,570
Interest rate swaps [Member] \| Derivatives designated as hedges [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Assets, at Fair Value	0
Interest rate swaps [Member] \| Derivatives designated as hedges [Member] \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Liabilities, at Fair Value	5,370	5,570
Loan level swaps [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	23,700	18,383
Liability Derivatives	23,699	18,380
Loan level swaps [Member] \| Not Designated as Hedging Instrument \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value	23,700	18,383
Loan level swaps [Member] \| Not Designated as Hedging Instrument \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value	23,699	18,380
Foreign exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	4,361	4,007
Liability Derivatives	4,333	3,984
Foreign exchange contracts \| Not Designated as Hedging Instrument \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value	4,361	4,007
Foreign exchange contracts \| Not Designated as Hedging Instrument \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value	4,333	3,984
Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Instrument Not Designated as a Hedge, Interest Rate Lock Commitments, Asset at Fair Value	386	295
Derivative Instrument Not Designated as a Hedge, Forward TBA Mortgage Contracts, Asset at Fair Value	0	0
Derivative Instrument Not Designated as a Hedge, Forward Sales Agreements, Asset at Fair Value	88	3
Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Instrument Not Designated as a Hedge, Interest Rate Lock Commitments, Liabilities at Fair Value	0	0
Derivative Instrument Not Designated as a Hedge, Forward TBA Mortgage Contracts, Liability at Fair Value	0	16
Derivative Instrument Not Designated as a Hedge, Forward Sales Agreements, Liabilities at Fair Value	$ 0	$ 0

Derivative Instrument Not Designated as a Hedge, Forward Sales Agreements, Asset at Fair Value

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- Definition

Derivative Instrument Not Designated as a Hedge, Forward Sales Agreements, Liabilities at Fair Value

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- Definition

Derivative Instrument Not Designated as a Hedge, Forward TBA Mortgage Contracts, Asset at Fair Value

+ References

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- Definition

Derivative Instrument Not Designated as a Hedge, Forward TBA Mortgage Contracts, Liability at Fair Value

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- Definition

Derivative Instrument Not Designated as a Hedge, Interest Rate Lock Commitments, Asset at Fair Value

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Derivative Instrument Not Designated as a Hedge, Interest Rate Lock Commitments, Liabilities at Fair Value

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226000-175313

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

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- Definition

Fair value as of the balance sheet date of all foreign currency derivative assets not designated as hedging instruments.

+ References

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- Definition

Fair value as of the balance sheet date of all foreign currency derivative liabilities not designated as hedging instruments.

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13433-108611

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Fair value as of the balance sheet date of all derivative assets not designated as hedging instruments.

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Fair value as of the balance sheet date of all derivative liabilities not designated as hedging instruments.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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