Derivatives and Hedging Activities (Derivative Financial Instruments included in OCI and Current Earnings) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent			$ 4,829
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	$ 14,306	$ 2,346	1,000
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Loss on Termination of Derivatives, before Tax	(684)
Derivatives designated as hedges: [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Excluded Component, Gain (Loss), Recognized in Earnings	0	0	0
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net		2,346
Derivatives not designated as hedges: [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other income	3,896	1,296	56
Other Expense [Member] | Derivatives designated as hedges: [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Excluded Component, Gain (Loss), Recognized in Earnings	0	0	0
Other Expense [Member] | Derivatives not designated as hedges: [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other income	(199)	(18)	(29)
Other Income [Member] | Derivatives not designated as hedges: [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other income	90	39	46
Mortgage banking income | Derivatives not designated as hedges: [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Increase Decrease In Fair Value Of Unhedged Derivative Instruments Relating To Residential Loans	4,005	1,275	39
Interest Expense [Member] | Derivatives designated as hedges: [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Excluded Component, Gain (Loss), Recognized in Earnings	0	0	0
Derivatives designated as hedges: [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent	$ 16,797	$ 10,331	$ 4,829