Investment Securities (Amortized Cost And Estimated Fair Value Of Investments In Debt Securities By Contractual Maturity) (Details) $ in Thousands	Mar. 31, 2021 USD ($)
U.S. Government Sponsored Entities Asset-Backed Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	$ 800,312
Securities Available-for-Sale, Total Fair value	$ 814,909
Debt Securities, Available-for-Sale, Weighted Average Yield	1.92%
US States and Political Subdivisions Debt Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	$ 96,354
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	$ 103,192
Debt Securities, Available-for-sale, Maturity, after Five Through Ten Years, Weighted Average Yield	3.75%
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	$ 182,322
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	$ 195,121
Debt Securities, Available-for-sale, Maturity, after 10 Years, Weighted Average Yield	3.67%
Debt Securities, Available-for-sale, Amortized Cost	$ 278,676
Securities Available-for-Sale, Total Fair value	$ 298,313
Debt Securities, Available-for-Sale, Weighted Average Yield	3.70%
Corporate Debt Securities
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	$ 2,000
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	$ 2,062
Debt Securities, Available-for-sale, Maturity, after Five Through Ten Years, Weighted Average Yield	4.00%

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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+ References

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping.

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping.

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Weighted average yield of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), maturing after tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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-Publisher SEC
-Name Industry Guide
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