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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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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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