Derivatives and Hedging Activities (FV of Derivative Financial Instruments and Classification on Balance Sheet) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 20,870	$ 17,318
Liability Derivatives	18,891	15,693
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	18,000	15,596
Derivative Asset, Fair Value, Gross Asset	21,040	17,476
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	17,825	15,429
Liability Derivatives	18,891	15,693
Interest rate swaps [Member] \| Derivatives designated as hedges [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Assets, at Fair Value	3,040	1,880
Interest rate swaps [Member] \| Derivatives designated as hedges [Member] \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Liabilities, at Fair Value	1,066	264
Loan level swaps [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	16,916	14,236
Loan level swaps [Member] \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	16,930	14,241
Foreign exchange contracts \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	914	1,202
Foreign exchange contracts \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	895	1,188
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	151	149
Derivative Instrument Not Designated as a Hedge, Forward Sales Agreements, Asset at Fair Value	19	9
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 Sales Agreements, Liabilities at Fair Value	$ 0	$ 0

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

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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=51824906&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=84234895&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=82849420&loc=SL20226000-175313

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 4D
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-URI http://asc.fasb.org/extlink&oid=82924980&loc=SL51823488-111719

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=82924980&loc=SL51823488-111719

Reference 2: 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=51824906&loc=SL20225862-175312

Reference 3: 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=84234895&loc=SL5624163-113959

Reference 4: 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=82849420&loc=SL20226000-175313

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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=84234895&loc=SL5624163-113959

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- Definition

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

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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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=77997519&loc=d3e13433-108611

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- Definition

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.

+ References

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