Derivative Financial Instruments (Fair Value of Derivatives by Balance Sheet Location) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Derivative assets	$ 3,582	$ 9,490
Derivative liabilities	4,043	10,347
Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	3,582	9,490
Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	4,043	10,347
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	0	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	378	0
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	134	187
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 lock commitments [Member] \| Not Designated as Hedging Instrument [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments	1,133	1,220
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	88	0
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	279	0
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	1,349	2,012
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	2,036	8,027
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	0	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	0	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	2,228	8,266
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	56
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	$ 69

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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