Derivatives and Hedging Activities (FV of Derivative Financial Instruments and Classification on Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total	$ 17,318	$ 22,331
Total	15,693	21,683
Other Assets [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	15,596	21,397
Total	17,476	22,761
Other Liabilities [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	15,429	21,176
Total	15,693	21,916
Interest rate derivatives
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total		740
Interest rate derivatives \| Derivatives designated as hedges: [Member] \| Other Assets [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Interest Rate Derivative Assets, at Fair Value	1,880	1,364
Interest rate derivatives \| Derivatives designated as hedges: [Member] \| Other Liabilities [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Interest rate derivatives	264	740
Loan level swaps
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total		18,629
Total		18,632
Loan level swaps \| Other Assets [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total	14,236	18,629
Loan level swaps \| Other Liabilities [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total	14,241	18,632
Foreign exchange contracts
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total		2,338
Total		2,311
Foreign exchange contracts \| Other Assets [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total	1,202	2,338
Foreign exchange contracts \| Other Liabilities [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total	1,188	2,311
Mortgage Derivatives \| Derivatives not designated as hedges: [Member] \| Other Assets [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Interest rate lock commitments	149	430
Forward sales agreements	9	0
Mortgage Derivatives \| Derivatives not designated as hedges: [Member] \| Other Liabilities [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Interest rate lock commitments	0	0
Forward sales agreements	$ 0	$ 233

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

+ 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

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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
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
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-Paragraph 4D
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-Publisher FASB
-Name Accounting Standards Codification
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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
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-Section 50
-Paragraph 4B
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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

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
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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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