Available-For-Sale And Held-To-Maturity Securities (Schedule Of Gross Unrealized Losses And The Estimated Fair Value By Length Of Time In A Loss Position) (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	$ (117,103)
Available-for-sale Securities, Estimated fair value, Less than 12 months	1,011,888
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(130,541)
Available-for-sale Securities, Estimated fair value, 12 months or more	595,663
Available-for-sale Securities, Gross unrealized losses, Total	(247,644)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,607,551
U.S. Government Agency Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(224)
Available-for-sale Securities, Estimated fair value, Less than 12 months	1,894
Available-for-sale Securities, Gross unrealized losses, 12 months or more	0
Available-for-sale Securities, Estimated fair value, 12 months or more	0
Available-for-sale Securities, Gross unrealized losses, Total	(224)
State And Municipal Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(40)
Available-for-sale Securities, Estimated fair value, Less than 12 months	2,314
Available-for-sale Securities, Gross unrealized losses, 12 months or more	0
Available-for-sale Securities, Estimated fair value, 12 months or more	0
Available-for-sale Securities, Gross unrealized losses, Total	(40)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	2,314
Corporate Fixed Income Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(48,271)
Available-for-sale Securities, Estimated fair value, Less than 12 months	413,188
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(37,154)
Available-for-sale Securities, Estimated fair value, 12 months or more	145,876
Available-for-sale Securities, Gross unrealized losses, Total	(85,425)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	559,064
Agency Mortgage Backed Securities [Member] \| Agency Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(61,691)
Available-for-sale Securities, Estimated fair value, Less than 12 months	451,197
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(81,651)
Available-for-sale Securities, Estimated fair value, 12 months or more	347,054
Available-for-sale Securities, Gross unrealized losses, Total	(143,342)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	798,251
Agency Mortgage Backed Securities [Member] \| U.S. Government Agency Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,894
Agency Mortgage Backed Securities [Member] \| Commercial [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(4,773)
Available-for-sale Securities, Estimated fair value, Less than 12 months	66,989
Available-for-sale Securities, Gross unrealized losses, 12 months or more	0
Available-for-sale Securities, Estimated fair value, 12 months or more	0
Available-for-sale Securities, Gross unrealized losses, Total	(4,773)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	66,989
Asset-Backed Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(2,104)
Available-for-sale Securities, Estimated fair value, Less than 12 months	76,306
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(11,736)
Available-for-sale Securities, Estimated fair value, 12 months or more	102,733
Available-for-sale Securities, Gross unrealized losses, Total	(13,840)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 179,039

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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