Derivatives (Net Gains (Losses) on Derivatives Designated as Hedges) (Details) - Fair Value Hedging - Derivative instruments designated as hedging instruments - Interest Expense - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Deposits
Derivative [Line Items]
Recognized on certificates of deposit	$ (357)	$ (1,434)	$ (1,719)	$ (2,695)
Interest rate contracts
Derivative [Line Items]
Recognized on interest rate swaps	$ 951	$ 1,634	$ 2,996	$ 2,854