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	Jun. 30, 2020 USD ($)
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	$ (22,251)
Available-for-sale Securities, Estimated fair value, Less than 12 months	1,110,236
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(16,156)
Available-for-sale Securities, Estimated fair value, 12 months or more	506,686
Available-for-sale Securities, Gross unrealized losses, Total	(38,407)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,616,922
Mortgage Backed Securities [Member] \| Agency [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(101)
Available-for-sale Securities, Estimated fair value, Less than 12 months	5,933
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(89)
Available-for-sale Securities, Estimated fair value, 12 months or more	12,619
Available-for-sale Securities, Gross unrealized losses, Total	(190)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	18,552
Mortgage Backed Securities [Member] \| Non-Agency [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(91)
Available-for-sale Securities, Estimated fair value, 12 months or more	788
Available-for-sale Securities, Gross unrealized losses, Total	(91)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	788
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	(40)
Available-for-sale Securities, Estimated fair value, Less than 12 months	27,658
Available-for-sale Securities, Gross unrealized losses, Total	(40)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	27,658
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	(22,110)
Available-for-sale Securities, Estimated fair value, Less than 12 months	1,076,645
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(15,976)
Available-for-sale Securities, Estimated fair value, 12 months or more	493,279
Available-for-sale Securities, Gross unrealized losses, Total	(38,086)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 1,569,924

Schedule of available for sale and held to maturity securities.

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This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922890-210455

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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 less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922890-210455

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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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 unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
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-Publisher FASB
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