Fair Value Of Financial Instruments (Schedule Of Estimated Fair Value Of Financial Instruments) (Details) - USD ($) $ in Thousands		Sep. 30, 2024	Dec. 31, 2023
Carrying Amount
Fair Value, Balance Sheet Grouping [Line Items]
Loans		$ 17,090,000	$ 17,205,479
Loans held for sale		1,707	4,177
Investment securities		9,475,131	9,941,786
Federal Funds Sold		10	5,025
Securities purchased under agreements to resell		475,000	450,000
Interest earning deposits with banks		2,642,048	2,239,010
Cash and due from banks		507,941	443,147
Derivative Asset		99,862	116,876
Assets held in trust for deferred compensation plan		21,989	20,538
Assets, Fair Value Financial Instruments		30,313,688	30,426,038
Non-interest bearing deposits		7,396,153	7,975,935
Savings, interest checking and money market deposits		15,216,557	14,512,273
Certificates of deposits		2,625,082	2,875,690
Federal funds purchased		113,630	261,305
Securities sold under agreements to repurchase		2,068,599	2,647,510
Other borrowings		10,178	1,366
Derivative Liabilities		26,896	37,899
Liabilities held in trust for deferred compensation plan		21,989	20,538
Financial Liabilities Fair Value Disclosure		27,479,084	28,332,516
Carrying Amount | Business Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		6,048,328	6,019,036
Carrying Amount | Real estate – construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		1,381,607	1,446,764
Carrying Amount | Business Real Estate Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,586,999	3,719,306
Carrying Amount | Personal Real Estate Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,043,391	3,026,041
Carrying Amount | Consumer Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,108,281	2,077,723
Carrying Amount | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		342,376	319,894
Carrying Amount | Credit Card Receivable [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		574,746	589,913
Carrying Amount | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		4,272	6,802
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		16,417,263	16,347,391
Loans held for sale		1,707	4,177
Investment securities		9,475,131	9,941,786
Federal Funds Sold		10	5,025
Securities purchased under agreements to resell		488,935	444,448
Interest earning deposits with banks		2,642,048	2,239,010
Cash and due from banks		507,941	443,147
Derivative Asset		99,862	116,876
Assets held in trust for deferred compensation plan		21,989	20,538
Assets, Fair Value Financial Instruments		29,654,886	29,562,398
Non-interest bearing deposits		7,396,153	7,975,935
Savings, interest checking and money market deposits		15,216,557	14,512,273
Certificates of deposits		2,670,740	2,916,627
Federal funds purchased		113,630	261,305
Securities sold under agreements to repurchase		2,071,881	2,650,951
Other borrowings		10,178	1,366
Derivative Liabilities		26,896	37,899
Liabilities held in trust for deferred compensation plan		21,989	20,538
Financial Liabilities Fair Value Disclosure		27,528,024	28,376,894
Estimate of Fair Value Measurement [Member] | Business Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		5,943,194	5,873,549
Estimate of Fair Value Measurement [Member] | Real estate – construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		1,355,750	1,420,522
Estimate of Fair Value Measurement [Member] | Business Real Estate Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,497,040	3,594,834
Estimate of Fair Value Measurement [Member] | Personal Real Estate Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,673,302	2,568,026
Estimate of Fair Value Measurement [Member] | Consumer Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,073,335	2,016,334
Estimate of Fair Value Measurement [Member] | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		339,322	317,013
Estimate of Fair Value Measurement [Member] | Credit Card Receivable [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		531,160	550,464
Estimate of Fair Value Measurement [Member] | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		4,160	6,649
Estimate of Fair Value Measurement [Member] | Level 1
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Loans held for sale		0	0
Investment securities		2,455,102	822,237
Federal Funds Sold		10	5,025
Securities purchased under agreements to resell		0	0
Interest earning deposits with banks		2,642,048	2,239,010
Cash and due from banks		507,941	443,147
Derivative Asset		0	0
Assets held in trust for deferred compensation plan		21,989	20,538
Assets, Fair Value Financial Instruments		5,627,090	3,529,957
Non-interest bearing deposits		7,396,153	7,975,935
Savings, interest checking and money market deposits		15,216,557	14,512,273
Certificates of deposits		0	0
Federal funds purchased		113,630	261,305
Securities sold under agreements to repurchase		0	0
Other borrowings		2,436	0
Derivative Liabilities		0	0
Liabilities held in trust for deferred compensation plan		21,989	20,538
Financial Liabilities Fair Value Disclosure		22,750,765	22,770,051
Estimate of Fair Value Measurement [Member] | Level 1 | Business Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 1 | Real estate – construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 1 | Business Real Estate Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 1 | Personal Real Estate Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 1 | Consumer Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 1 | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 1 | Credit Card Receivable [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 1 | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 2
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Loans held for sale		1,707	4,177
Investment securities		6,802,535	8,896,129
Federal Funds Sold		0	0
Securities purchased under agreements to resell		0	0
Interest earning deposits with banks		0	0
Cash and due from banks		0	0
Derivative Asset		99,565	116,710
Assets held in trust for deferred compensation plan		0	0
Assets, Fair Value Financial Instruments		6,903,807	9,017,016
Non-interest bearing deposits		0	0
Savings, interest checking and money market deposits		0	0
Certificates of deposits		0	0
Federal funds purchased		0	0
Securities sold under agreements to repurchase		0	0
Other borrowings		7,742	1,366
Derivative Liabilities		26,755	37,704
Liabilities held in trust for deferred compensation plan		0	0
Financial Liabilities Fair Value Disclosure		34,497	39,070
Estimate of Fair Value Measurement [Member] | Level 2 | Business Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 2 | Real estate – construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 2 | Business Real Estate Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 2 | Personal Real Estate Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 2 | Consumer Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 2 | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 2 | Credit Card Receivable [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Level 2 | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimate of Fair Value Measurement [Member] | Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping [Line Items]
Loans		16,417,263	16,347,391
Loans held for sale		0	0
Investment securities		217,494	223,420
Federal Funds Sold		0	0
Securities purchased under agreements to resell		488,935	444,448
Interest earning deposits with banks		0	0
Cash and due from banks		0	0
Derivative Asset		297	166
Assets held in trust for deferred compensation plan		0	0
Assets, Fair Value Financial Instruments		17,123,989	17,015,425
Non-interest bearing deposits		0	0
Savings, interest checking and money market deposits		0	0
Certificates of deposits		2,670,740	2,916,627
Federal funds purchased		0	0
Securities sold under agreements to repurchase		2,071,881	2,650,951
Other borrowings		0	0
Derivative Liabilities		141	195
Liabilities held in trust for deferred compensation plan		0	0
Financial Liabilities Fair Value Disclosure		4,742,762	5,567,773
Estimate of Fair Value Measurement [Member] | Significant Unobservable Inputs (Level 3) | Business Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		5,943,194	5,873,549
Estimate of Fair Value Measurement [Member] | Significant Unobservable Inputs (Level 3) | Real estate – construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		1,355,750	1,420,522
Estimate of Fair Value Measurement [Member] | Significant Unobservable Inputs (Level 3) | Business Real Estate Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,497,040	3,594,834
Estimate of Fair Value Measurement [Member] | Significant Unobservable Inputs (Level 3) | Personal Real Estate Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,673,302	2,568,026
Estimate of Fair Value Measurement [Member] | Significant Unobservable Inputs (Level 3) | Consumer Loan [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,073,335	2,016,334
Estimate of Fair Value Measurement [Member] | Significant Unobservable Inputs (Level 3) | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		339,322	317,013
Estimate of Fair Value Measurement [Member] | Significant Unobservable Inputs (Level 3) | Credit Card Receivable [Member]
Fair Value, Balance Sheet Grouping [Line Items]
Loans		531,160	550,464
Estimate of Fair Value Measurement [Member] | Significant Unobservable Inputs (Level 3) | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		4,160	6,649
Federal Funds Sold		10	5,025
Securities purchased under agreements to resell		475,000	450,000
Interest earning deposits with banks		2,642,048	2,239,010
Cash and due from banks		507,941	443,147
Derivative Asset	[1]	99,862	116,876
Assets held in trust for deferred compensation plan		21,989	20,538
Non-interest bearing deposits		7,396,153	7,975,935
Savings, interest checking and money market deposits		15,216,557	14,512,273
Other borrowings		10,201	1,404
Derivative Liabilities	[1]	26,896	37,899
Liabilities held in trust for deferred compensation plan		21,989	20,538
Level 1
Fair Value, Balance Sheet Grouping [Line Items]
Derivative Asset	[1]	0	0
Assets held in trust for deferred compensation plan		21,989	20,538
Derivative Liabilities	[1]	0	0
Liabilities held in trust for deferred compensation plan		21,989	20,538
Level 2
Fair Value, Balance Sheet Grouping [Line Items]
Derivative Asset	[1]	99,565	116,710
Assets held in trust for deferred compensation plan		0	0
Derivative Liabilities	[1]	26,755	37,704
Liabilities held in trust for deferred compensation plan		0	0
Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping [Line Items]
Derivative Asset	[1]	297	166
Assets held in trust for deferred compensation plan		0	0
Derivative Liabilities	[1]	141	195
Liabilities held in trust for deferred compensation plan		$ 0	$ 0

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