Investments (Amortized Cost And Estimated Fair Value Of Debt Securities By Contractual Maturity) (Details) $ in Thousands	Jun. 30, 2020 USD ($)
Securities Available-for-Sale, Amortized Cost
Securities Available-for-Sale, Due in one year or less, Amortized Cost	$ 2,050
Securities Available-for-Sale, Due after one year through five years, Amortized Cost	15,327
Securities Available-for-Sale, Due after five years through ten years, Amortized Cost	294,981
Securities Available-for-Sale, Due after ten years, Amortized Cost	691,825
Securities Available-for-Sale, Amortized Cost, Total	1,004,183
Securities Available-for-Sale, Estimated Fair Value
Securities Available-for-Sale, Due in one year or less, Estimated Fair Value	2,062
Securities Available-for-Sale, Due after one year through five years, Estimated Fair Value	15,900
Securities Available-for-Sale, Due after five years through ten years, Estimated Fair Value	312,351
Securities Available-for-Sale, Due after ten years, Estimated Fair Value	722,631
Securities Available-for-Sale, Estimated Fair Value, Total	$ 1,052,944

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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