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Derivative Instruments (Schedule Of Notional Amounts Of Derivative Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Derivative, Notional Amount	$ 3,015,189	$ 4,525,856
Interest Rate Swaps [Member]
Derivative [Line Items]
Derivative, Notional Amount	2,367,017	2,606,181
Interest Rate Floor [Member]
Derivative [Line Items]
Derivative, Notional Amount	0	1,500,000
Interest Rate Caps [Member]
Derivative [Line Items]
Derivative, Notional Amount	103,028	59,316
Credit Risk Participation Agreements [Member]
Derivative [Line Items]
Derivative, Notional Amount	381,170	316,225
Foreign Exchange Contracts [Member]
Derivative [Line Items]
Derivative, Notional Amount	7,431	10,936
Mortgage Loan Commitments [Member]
Derivative [Line Items]
Derivative, Notional Amount	67,543	13,755
Mortgage Loan Forward Sale Contracts [Member]
Derivative [Line Items]
Derivative, Notional Amount	0	1,943
Forward Contracts [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 89,000	$ 17,500

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- Definition

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+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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