Derivative Financial Instruments Fair Value Gains and Losses on Derivative Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Mortgage Banking Income [Member] | Interest rate lock with customers [Member]
Derivative [Line Items]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	$ (1,287)	$ 1,203	$ (165)	$ 1,592
Mortgage Banking Income [Member] | Forward Commitments [Member]
Derivative [Line Items]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	2,291	(1,503)	2,845	(3,001)
Other Income [Member]
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Income, Net	967	(293)	2,886	(1,478)
Other Income [Member] | Interest Rate Swap with Customer [Member]
Derivative [Line Items]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	(9,839)	6,135	(435)	10,340
Other Income [Member] | Interest Rate Swap with Counterparty [Member]
Derivative [Line Items]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	9,839	(6,135)	435	(10,340)
Other Income [Member] | Foreign Exchange Contracts With Customer [Member]
Derivative [Line Items]
Gain (Loss) on Foreign Currency Derivatives Recorded in Earnings, Net	(748)	105	(181)	297
Other Income [Member] | Foreign Exchange Contracts With Correspondent Banks [Member]
Derivative [Line Items]
Gain (Loss) on Foreign Currency Derivatives Recorded in Earnings, Net	$ 711	$ (98)	$ 387	$ (366)