Investment Securities (Schedule Of Fair Value And Unrealized Losses Of Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Investment Holdings [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 2,050,017	$ 249,015
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	44,481	792
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	160,483	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	7,545	0
Debt Securities, Available-for-sale, Unrealized Loss Position	2,210,500	249,015
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	52,026	792
U.S. Treasury and agencies
Investment Holdings [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	197,529	29,493
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	2,749	312
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	28,378	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	1,446	0
Debt Securities, Available-for-sale, Unrealized Loss Position	225,907	29,493
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	4,195	312
Obligations of states and political subdivisions
Investment Holdings [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	75,200	4,357
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	1,153	31
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	2,162	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	135	0
Debt Securities, Available-for-sale, Unrealized Loss Position	77,362	4,357
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	1,288	31
Residential mortgage-backed securities and collateralized mortgage obligations
Investment Holdings [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,777,288	215,165
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	40,579	449
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	129,943	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	5,964	0
Debt Securities, Available-for-sale, Unrealized Loss Position	1,907,231	215,165
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 46,543	$ 449

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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-Name Accounting Standards Codification
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