Derivatives and Hedging Activity - Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Fair value of derivative instruments
Fair Value of Derivatives in an Asset Position	$ 89,361	$ 45,091
Fair Value of Derivatives in a Liability Position	3,904	5,196
Derivatives designated as hedging instruments
Fair value of derivative instruments
Fair Value of Derivatives in an Asset Position	30	57
Fair Value of Derivatives in a Liability Position	56	122
Derivatives not designated as hedging instruments
Fair value of derivative instruments
Fair Value of Derivatives in an Asset Position	89,331	45,034
Fair Value of Derivatives in a Liability Position	3,848	5,074
Interest rate swaps | Derivatives designated as hedging instruments
Fair value of derivative instruments
Fair Value of Derivatives in an Asset Position	30	57
Fair Value of Derivatives in a Liability Position	56	122
Interest rate swaps | Derivatives not designated as hedging instruments
Fair value of derivative instruments
Fair Value of Derivatives in an Asset Position	26,591	2,360
Fair Value of Derivatives in a Liability Position	3,484	4,970
Foreign exchange contracts | Derivatives not designated as hedging instruments
Fair value of derivative instruments
Fair Value of Derivatives in an Asset Position	62,295	41,137
Fair Value of Derivatives in a Liability Position	364	104
Credit index instruments | Derivatives not designated as hedging instruments
Fair value of derivative instruments
Fair Value of Derivatives in an Asset Position	$ 445	$ 1,537