Derivatives (Hedged Items Currently Designated) (Details) - Derivative instruments designated as hedging instruments - Fair Value Hedging - Certificates of deposits - Interest rate contracts - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Hedged liability, fair value hedge, carrying value	$ (27,804)	$ (26,877)
Hedged liability, fair value hedge, cumulative decrease, carrying value	$ 2,880	$ 4,141