Derivative Financial Instruments (Fair Value of Derivatives by Balance Sheet Location) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Total derivative assets	$ 4,457	$ 3,582
Total derivative liabilities	5,487	4,043
Other assets [Member]
Derivatives, Fair Value [Line Items]
Total derivative assets	4,457	3,582
Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Total derivative liabilities	5,487	4,043
Derivatives Designated as Cash Flow Hedging Instruments [Member] \| Interest rate swaps [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset designated as a cash flow hedge	0	0
Derivatives Designated as Cash Flow Hedging Instruments [Member] \| Interest rate swaps [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability designated as a cash flow hedge	537	378
Derivatives Designated as Cash Flow Hedging Instruments [Member] \| Interest rate caps [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset designated as a cash flow hedge	44	134
Derivatives Designated as Cash Flow Hedging Instruments [Member] \| Interest rate caps [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability designated as a cash flow hedge	0	0
Derivatives Designated as Cash Flow Hedging Instruments [Member] \| Interest rate floors [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset designated as a cash flow hedge	389	0
Derivatives Designated as Cash Flow Hedging Instruments [Member] \| Interest rate floors [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability designated as a cash flow hedge	0	0
Not Designated as Hedging Instrument [Member] \| Interest Rate Commitments [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated	1,679	1,133
Not Designated as Hedging Instrument [Member] \| Interest Rate Commitments [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated	27	88
Not Designated as Hedging Instrument [Member] \| Commitments to sell mortgage loans [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated	27	279
Not Designated as Hedging Instrument [Member] \| Commitments to sell mortgage loans [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated	2,477	1,349
Not Designated as Hedging Instrument [Member] \| Interest rate swaps with customers [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated	2,318	2,036
Not Designated as Hedging Instrument [Member] \| Interest rate swaps with customers [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated	0	0
Not Designated as Hedging Instrument [Member] \| Mirror swaps with counterparties [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated	0	0
Not Designated as Hedging Instrument [Member] \| Mirror swaps with counterparties [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated	2,446	2,228
Not Designated as Hedging Instrument [Member] \| Risk participation-out agreement [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated	0	0
Not Designated as Hedging Instrument [Member] \| Risk participation-in agreement [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated	$ 0	$ 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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- Definition

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

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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.

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

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Fair value as of the balance sheet date of all interest rate derivative assets designated as cash flow hedging instruments.

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- Definition

Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

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