Derivatives and Hedging Activities (FV of Derivative Financial Instruments and Classification on Balance Sheet) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 32,936	$ 26,113
Liability Derivatives	19,762	17,523
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	20,056	17,355
Derivative Asset, Fair Value, Gross Asset	33,192	26,310
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	19,762	17,132
Liability Derivatives	19,762	17,523
Interest rate swaps [Member] \| Derivatives designated as hedges [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Assets, at Fair Value	13,136	8,955
Interest rate swaps [Member] \| Derivatives designated as hedges [Member] \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Liabilities, at Fair Value	0	391
Loan level swaps [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	17,660	15,580
Loan level swaps [Member] \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	17,660	15,584
Foreign exchange contracts \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	2,140	1,578
Foreign exchange contracts \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	2,102	1,548
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	128	91
Derivative Instrument Not Designated as a Hedge, Forward Sales Agreements, Asset at Fair Value	128	106
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

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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

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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.

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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

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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://fasb.org/us-gaap/role/ref/legacyRef
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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.

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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

No definition available.

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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.

+ References

No definition available.

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