Derivative Financial Instruments (Fair Value of Derivatives by Balance Sheet Location) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative assets	$ 2,759	$ 3,582
Derivative liabilities	3,047	4,043
Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	2,759	3,582
Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	3,047	4,043
Interest rate swaps [Member] \| Designated as Hedging Instrument [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge asset at fair value	213	0
Interest rate swaps [Member] \| Designated as Hedging Instrument [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge liability at fair value	14	378
Interest rate caps [Member] \| Designated as Hedging Instrument [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge asset at fair value	25	134
Interest rate caps [Member] \| Designated as Hedging Instrument [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge liability at fair value	0	0
Interest rate floors [Member] \| Designated as Hedging Instrument [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge asset at fair value	110	0
Interest rate floors [Member] \| Designated as Hedging Instrument [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge liability at fair value	0	0
Interest rate lock commitments [Member] \| Not Designated as Hedging Instrument [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments	965	1,133
Interest rate lock commitments [Member] \| Not Designated as Hedging Instrument [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments	20	88
Commitments to sell mortgage loans [Member] \| Not Designated as Hedging Instrument [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments	26	279
Commitments to sell mortgage loans [Member] \| Not Designated as Hedging Instrument [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments	1,424	1,349
Interest rate swaps with customers [Member] \| Not Designated as Hedging Instrument [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments	268	2,036
Interest rate swaps with customers [Member] \| Not Designated as Hedging Instrument [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments	1,295	0
Mirror swaps with counterparties [Member] \| Not Designated as Hedging Instrument [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments	1,152	0
Mirror swaps with counterparties [Member] \| Not Designated as Hedging Instrument [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments	268	2,228
Risk participation-out agreement [Member] \| Not Designated as Hedging Instrument [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments	0	0
Risk participation-in agreement [Member] \| Not Designated as Hedging Instrument [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments	0	0
Foreign exchange contract [Member] \| Not Designated as Hedging Instrument [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments	0	0
Foreign exchange contract [Member] \| Not Designated as Hedging Instrument [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments	$ 26	$ 0

Fair value, after the 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 not subject to a master netting arrangement and not elected to be offset.

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