Investments (Amortized Cost And Estimated Fair Value Of Debt Securities By Contractual Maturity) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Investments [Abstract]
Securities Available-for-Sale, Due in one year or less, Cost	$ 3,024
Securities Available-for-Sale, Due after one year through five years, Cost	41,823
Securities Available-for-Sale, Due after five years through ten years, Cost	269,825
Securities Available-for-Sale, Due after ten years, Cost	1,074,646
Securities Available-for-Sale, Cost, Total	1,389,318	$ 1,128,163
Securities Available-for-Sale, Due in one year or less, Estimated Fair Value	3,089
Securities Available-for-Sale, Due after one year through five years, Estimated Fair Value	43,746
Securities Available-for-Sale, Due after five years through ten years, Estimated Fair Value	279,486
Securities Available-for-Sale, Due after ten years, Estimated Fair Value	1,081,844
Debt Securities, Available-for-sale, Total	$ 1,408,165	$ 1,176,797

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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