Commitments and Contingencies (Summary of Contractual and Notional Amounts of Financial Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financial Instruments [Line Items]
Contractual Amounts Of Financial Instrument	$ 728,721	$ 739,860
Commitments to Extend Credit [Member]
Financial Instruments [Line Items]
Contractual Amounts Of Financial Instrument	723,986	734,649
Standby Letters of Credit [Member]
Financial Instruments [Line Items]
Contractual Amounts Of Financial Instrument	$ 4,735	$ 5,211