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Derivative Instruments (Schedule Of Notional Amounts Of Derivative Instruments) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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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 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 + Details
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