Derivative Financial Instruments (Fair Value of Derivatives by Balance Sheet Location) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Total derivative assets	$ 13,489	$ 2,759
Total derivative liabilities	11,568	3,047
Other assets [Member]
Derivatives, Fair Value [Line Items]
Total derivative assets	13,489	2,759
Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Total derivative liabilities	11,568	3,047
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	67	25
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 swaps [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset designated as a cash flow hedge	1,313	213
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	0	14
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	90	110
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 swaps with customers [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated	137	268
Not Designated as Hedging Instrument [Member] \| Interest rate swaps with customers [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated	10,978	1,295
Not Designated as Hedging Instrument [Member] \| Mirror swaps with counterparties [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated	10,787	1,152
Not Designated as Hedging Instrument [Member] \| Mirror swaps with counterparties [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated	137	268
Not Designated as Hedging Instrument [Member] \| Risk participation agreements [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated	0	0
Not Designated as Hedging Instrument [Member] \| Risk participation agreements [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated	0	0
Not Designated as Hedging Instrument [Member] \| Foreign exchange contracts [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated	20	0
Not Designated as Hedging Instrument [Member] \| Foreign exchange contracts [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated	0	26
Not Designated as Hedging Instrument [Member] \| Interest rate lock commitments [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated	931	965
Not Designated as Hedging Instrument [Member] \| Interest rate lock commitments [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated	0	20
Not Designated as Hedging Instrument [Member] \| Forward sale commitments [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated	144	26
Not Designated as Hedging Instrument [Member] \| Forward sale commitments [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated	$ 453	$ 1,424

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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