Noninterest Income Foreign Exchange Fees (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Gains and Losses on Derivatives [Abstract]
Brokerage Commissions Revenue	$ 31,202	$ 22,424
Forward Contract Commissions	2,485	3,601
Option Premium Fees	140	222
Foreign exchange fees	$ 33,827	$ 26,247