Derivative Instruments (Schedule Of Fair Values Of Derivative Instruments) (Details) - USD ($) $ in Thousands		Jun. 30, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Derivative Assets	[1]	$ 269,010	$ 105,674
Derivative Liabilities	[1]	(21,373)	(10,219)
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets		162,426	67,192
Derivative Liabilities		0	0
Designated as Hedging Instrument [Member] | Interest Rate Floor [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets		162,426	67,192
Derivative Liabilities		0	0
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets		106,584	38,482
Derivative Liabilities		(21,373)	(10,219)
Not Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets		103,543	37,774
Derivative Liabilities		(20,053)	(9,916)
Not Designated as Hedging Instrument [Member] | Interest Rate Caps [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets		28	4
Derivative Liabilities		(28)	(4)
Not Designated as Hedging Instrument [Member] | Credit Risk Participation Agreements [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets		435	140
Derivative Liabilities		(1,094)	(230)
Not Designated as Hedging Instrument [Member] | Foreign Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets		26	97
Derivative Liabilities		(43)	(32)
Not Designated as Hedging Instrument [Member] | Mortgage Loan Commitments [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets		2,547	459
Derivative Liabilities		0	0
Not Designated as Hedging Instrument [Member] | Mortgage Loan Forward Sale Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets		3	6
Derivative Liabilities		0	(2)
Not Designated as Hedging Instrument [Member] | Forward TBA Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets		2	2
Derivative Liabilities		$ (155)	$ (35)

[1] * The fair value of each class of derivative is shown in Note 11.