Investments (Amortized Cost And Fair Value Of Debt Securities, By Contractual Maturity) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	$ 535,101	$ 525,717
Fair Value	511,477	$ 529,811
Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Due in one year or less, Amortized cost	1,667
Due after one year through five years, Amortized cost	8,933
Due after five years through ten years, Amortized cost	144,994
Due after ten years, Amortized cost	160,343
Amortized cost	315,937
Due in one year or less, Fair value	1,682
Due after one year through five years, Fair value	8,848
Due after five years through ten years, Fair value	137,312
Due after ten years, Fair value	151,703
Fair Value	299,545
Mortgage And Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Mortgage-backed securities, Amortized cost	219,164
Mortgage-backed securities, Fair value	$ 211,932

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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