Derivative Financial Instruments (Fair Value of Derivatives by Balance Sheet Location) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Total derivative assets	$ 20,242	$ 2,759
Total derivative liabilities	17,822	3,047
Other assets [Member]
Derivatives, Fair Value [Line Items]
Total derivative assets	20,242	2,759
Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Total derivative liabilities	17,822	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	83	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	1,947	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	14	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	33	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	17,522	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	17,342	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	33	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	37	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	618	965
Not Designated as Hedging Instrument [Member] \| Interest rate lock commitments [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated	1	20
Not Designated as Hedging Instrument [Member] \| Forward sale commitments [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated	168	26
Not Designated as Hedging Instrument [Member] \| Forward sale commitments [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated	$ 266	$ 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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