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Derivative Instruments (Schedule Of Fair Values Of Derivative Instruments) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |  |
Other assets | [1] | $ 89,889 | $ 105,674
Other liabilities | [1] | (18,675) | (10,219)
Designated as Hedging Instrument [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Other assets |  | 0 | 67,192
Other liabilities |  | 0 | 0
Designated as Hedging Instrument [Member] | Interest Rate Floor [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Other assets |  | 0 | 67,192
Other liabilities |  | 0 | 0
Not Designated as Hedging Instrument [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Other assets |  | 89,889 | 38,482
Other liabilities |  | (18,675) | (10,219)
Not Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Other assets |  | 86,389 | 37,774
Other liabilities |  | (17,199) | (9,916)
Not Designated as Hedging Instrument [Member] | Interest Rate Caps [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Other assets |  | 1 | 4
Other liabilities |  | (1) | (4)
Not Designated as Hedging Instrument [Member] | Credit Risk Participation Agreements [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Other assets |  | 216 | 140
Other liabilities |  | (701) | (230)
Not Designated as Hedging Instrument [Member] | Foreign Exchange Contracts [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Other assets |  | 57 | 97
Other liabilities |  | (103) | (32)
Not Designated as Hedging Instrument [Member] | Mortgage Loan Commitments [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Other assets |  | 3,226 | 459
Other liabilities |  | 0 | 0
Not Designated as Hedging Instrument [Member] | Mortgage Loan Forward Sale Contracts [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Other assets |  | 0 | 6
Other liabilities |  | 0 | (2)
Not Designated as Hedging Instrument [Member] | Forward Contracts [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Other assets |  | 0 | 2
Other liabilities |  | $ (671) | $ (35)
[1] | The fair value of each class of derivative is shown in Note 19.

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