Intangible Assets (Carrying and Fair Value of MSRs) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Net carrying value, fair value of MSRs and loans Corporation servicing for others
Loans serviced for others that have servicing rights capitalized	$ 2,047,435	$ 2,082,899	$ 2,062,544
Mortgage servicing rights [Member]
Net carrying value, fair value of MSRs and loans Corporation servicing for others
Net carrying value of MSRs	10,478	11,122	11,583
Fair value of MSRs	$ 13,909	$ 15,542	$ 14,378