Derivatives - (FV of Derivatives on the Balance Sheet) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Asset derivatives fair value	$ 21,496	$ 10,489
Liability derivatives fair value	121	1,167
Not Designated as Hedging Instrument, Economic Hedge [Member]
Derivative [Line Items]
Asset derivatives fair value	4,515	2,616
Liability derivatives fair value	3,780	2,591
Interest Rate Lock Commitments [Member] | Not Designated as Hedging Instrument, Economic Hedge [Member]
Derivative [Line Items]
Asset derivatives fair value	110,700
Other assets [Member] | Interest rate products [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
Asset derivatives fair value	21,496	10,489
Liability derivatives fair value	121
Other assets [Member] | Interest rate products [Member] | Not Designated as Hedging Instrument, Economic Hedge [Member]
Derivative [Line Items]
Asset derivatives fair value	3,199	2,483
Liability derivatives fair value	3,179
Other assets [Member] | Interest Rate Lock Commitments [Member] | Not Designated as Hedging Instrument, Economic Hedge [Member]
Derivative [Line Items]
Asset derivatives fair value	1,219	128
Liability derivatives fair value	312
Other assets [Member] | Forward Contracts [Member] | Not Designated as Hedging Instrument, Economic Hedge [Member]
Derivative [Line Items]
Asset derivatives fair value	97	5
Liability derivatives fair value	$ 289
Other liabilities [Member] | Interest rate products [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
Liability derivatives fair value		1,167
Other liabilities [Member] | Interest rate products [Member] | Not Designated as Hedging Instrument, Economic Hedge [Member]
Derivative [Line Items]
Liability derivatives fair value		2,584
Other liabilities [Member] | Forward Contracts [Member] | Not Designated as Hedging Instrument, Economic Hedge [Member]
Derivative [Line Items]
Liability derivatives fair value		$ 7