Investments (Amortized Cost And Fair Value Of Debt Securities, By Contractual Maturity) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Investments [Abstract]
Due in one year or less, Amortized cost	$ 4,369
Due after one year through five years, Amortized cost	21,250
Due after five years through ten years, Amortized cost	216,196
Due after ten years, Amortized cost	27,453
Amortized Cost Contractual Maturities Subtotal	269,268
Mortgage-backed securities, Amortized cost	115,101
Available-for-sale Securities, Debt Maturities, Amortized cost	384,369
Due in one year or less, Fair value	4,388
Due after one year through five years, Fair value	21,857
Due after five years through ten years, Fair value	225,142
Due after ten years, Fair value	28,529
Fair Value Contractual Maturities Subtotal	279,916
Mortgage-backed securities, Fair value	117,024
Available-for-sale Securities, Debt Securities, Fair Value	$ 396,940	$ 187,433

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