Fair Value Of Financial Instruments (Schedule Of Estimated Fair Value Of Financial Instruments) (Details) - USD ($) $ in Thousands		Sep. 30, 2023	Dec. 31, 2022
Carrying Amount
Fair Value, Balance Sheet Grouping [Line Items]
Loans		$ 17,129,326	$ 16,303,131
Loans held for sale		5,120	4,964
Investment securities		10,132,637	12,511,649
Federal Funds Sold		2,735	49,505
Securities purchased under agreements to resell		450,000	825,000
Interest earning deposits with banks		1,847,641	389,140
Cash and due from banks		358,010	452,496
Derivative Asset		112,182	60,492
Assets held in trust for deferred compensation plan		18,859	17,856
Assets, Fair Value Financial Instruments		30,056,510	30,614,233
Non-interest bearing deposits		7,961,402	10,066,356
Savings, interest checking and money market deposits		14,154,275	15,126,981
Certificates of deposits		2,974,780	994,103
Federal funds purchased		506,355	159,860
Securities sold under agreements to repurchase		2,238,826	2,681,874
Other borrowings		503,547	8,831
Derivative Liabilities		58,718	54,984
Liabilities held in trust for deferred compensation plan		18,859	17,856
Financial Liabilities Fair Value Disclosure		28,416,762	29,110,845
Carrying Amount | Business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		5,908,330	5,661,725
Carrying Amount | Real estate - construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		1,539,566	1,361,095
Carrying Amount | Real estate - business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,647,168	3,406,981
Carrying Amount | Real estate - personal
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,024,639	2,918,078
Carrying Amount | Consumer
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,125,804	2,059,088
Carrying Amount | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		305,237	297,207
Carrying Amount | Consumer credit card
Fair Value, Balance Sheet Grouping [Line Items]
Loans		574,829	584,000
Carrying Amount | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,753	14,957
Estimated Fair Value at September 30, 2023
Fair Value, Balance Sheet Grouping [Line Items]
Loans		16,299,564	15,645,261
Loans held for sale		5,120	4,964
Investment securities		10,132,637	12,511,649
Federal Funds Sold		2,735	49,505
Securities purchased under agreements to resell		439,056	795,574
Interest earning deposits with banks		1,847,641	389,140
Cash and due from banks		358,010	452,496
Derivative Asset		112,182	60,492
Assets held in trust for deferred compensation plan		18,859	17,856
Assets, Fair Value Financial Instruments		29,215,804	29,926,937
Non-interest bearing deposits		7,961,402	10,066,356
Savings, interest checking and money market deposits		14,154,275	15,126,981
Certificates of deposits		3,003,240	982,613
Federal funds purchased		506,355	159,860
Securities sold under agreements to repurchase		2,241,706	2,684,471
Other borrowings		503,547	8,831
Derivative Liabilities		58,718	54,984
Liabilities held in trust for deferred compensation plan		18,859	17,856
Financial Liabilities Fair Value Disclosure		28,448,102	29,101,952
Estimated Fair Value at September 30, 2023 | Business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		5,733,548	5,506,128
Estimated Fair Value at September 30, 2023 | Real estate - construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		1,520,702	1,347,328
Estimated Fair Value at September 30, 2023 | Real estate - business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,486,455	3,289,655
Estimated Fair Value at September 30, 2023 | Real estate - personal
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,652,514	2,654,423
Estimated Fair Value at September 30, 2023 | Consumer
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,059,484	1,999,788
Estimated Fair Value at September 30, 2023 | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		302,428	295,005
Estimated Fair Value at September 30, 2023 | Consumer credit card
Fair Value, Balance Sheet Grouping [Line Items]
Loans		540,766	538,268
Estimated Fair Value at September 30, 2023 | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,667	14,666
Estimated Fair Value at September 30, 2023 | Level 1
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Loans held for sale		0	0
Investment securities		953,429	1,041,616
Federal Funds Sold		2,735	49,505
Securities purchased under agreements to resell		0	0
Interest earning deposits with banks		1,847,641	389,140
Cash and due from banks		358,010	452,496
Derivative Asset		0	0
Assets held in trust for deferred compensation plan		18,859	17,856
Assets, Fair Value Financial Instruments		3,180,674	1,950,613
Non-interest bearing deposits		7,961,402	10,066,356
Savings, interest checking and money market deposits		14,154,275	15,126,981
Certificates of deposits		0	0
Federal funds purchased		506,355	159,860
Securities sold under agreements to repurchase		0	0
Other borrowings		0	0
Derivative Liabilities		0	0
Liabilities held in trust for deferred compensation plan		18,859	17,856
Financial Liabilities Fair Value Disclosure		22,640,891	25,371,053
Estimated Fair Value at September 30, 2023 | Level 1 | Business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 1 | Real estate - construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 1 | Real estate - business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 1 | Real estate - personal
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 1 | Consumer
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 1 | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 1 | Consumer credit card
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 1 | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 2
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Loans held for sale		5,120	4,964
Investment securities		8,947,478	11,244,592
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		112,136	60,458
Assets held in trust for deferred compensation plan		0	0
Assets, Fair Value Financial Instruments		9,064,734	11,310,014
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		3,547	8,831
Derivative Liabilities		58,674	54,865
Liabilities held in trust for deferred compensation plan		0	0
Financial Liabilities Fair Value Disclosure		62,221	63,696
Estimated Fair Value at September 30, 2023 | Level 2 | Business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 2 | Real estate - construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 2 | Real estate - business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 2 | Real estate - personal
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 2 | Consumer
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 2 | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 2 | Consumer credit card
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Level 2 | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at September 30, 2023 | Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping [Line Items]
Loans		16,299,564	15,645,261
Loans held for sale		0	0
Investment securities		231,730	225,441
Federal Funds Sold		0	0
Securities purchased under agreements to resell		439,056	795,574
Interest earning deposits with banks		0	0
Cash and due from banks		0	0
Derivative Asset		46	34
Assets held in trust for deferred compensation plan		0	0
Assets, Fair Value Financial Instruments		16,970,396	16,666,310
Non-interest bearing deposits		0	0
Savings, interest checking and money market deposits		0	0
Certificates of deposits		3,003,240	982,613
Federal funds purchased		0	0
Securities sold under agreements to repurchase		2,241,706	2,684,471
Other borrowings		500,000	0
Derivative Liabilities		44	119
Liabilities held in trust for deferred compensation plan		0	0
Financial Liabilities Fair Value Disclosure		5,744,990	3,667,203
Estimated Fair Value at September 30, 2023 | Significant Unobservable Inputs (Level 3) | Business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		5,733,548	5,506,128
Estimated Fair Value at September 30, 2023 | Significant Unobservable Inputs (Level 3) | Real estate - construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		1,520,702	1,347,328
Estimated Fair Value at September 30, 2023 | Significant Unobservable Inputs (Level 3) | Real estate - business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,486,455	3,289,655
Estimated Fair Value at September 30, 2023 | Significant Unobservable Inputs (Level 3) | Real estate - personal
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,652,514	2,654,423
Estimated Fair Value at September 30, 2023 | Significant Unobservable Inputs (Level 3) | Consumer
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,059,484	1,999,788
Estimated Fair Value at September 30, 2023 | Significant Unobservable Inputs (Level 3) | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		302,428	295,005
Estimated Fair Value at September 30, 2023 | Significant Unobservable Inputs (Level 3) | Consumer credit card
Fair Value, Balance Sheet Grouping [Line Items]
Loans		540,766	538,268
Estimated Fair Value at September 30, 2023 | Significant Unobservable Inputs (Level 3) | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,667	14,666
Federal Funds Sold		2,735	49,505
Securities purchased under agreements to resell		450,000	825,000
Interest earning deposits with banks		1,847,641	389,140
Cash and due from banks		358,010	452,496
Derivative Asset	[1]	112,182	60,492
Assets held in trust for deferred compensation plan		18,859	17,856
Non-interest bearing deposits		7,961,402	10,066,356
Savings, interest checking and money market deposits		14,154,275	15,126,981
Other borrowings		503,589	9,672
Derivative Liabilities	[1]	58,718	54,984
Liabilities held in trust for deferred compensation plan		18,859	17,856
Level 1
Fair Value, Balance Sheet Grouping [Line Items]
Derivative Asset	[1]	0	0
Assets held in trust for deferred compensation plan		18,859	17,856
Derivative Liabilities	[1]	0	0
Liabilities held in trust for deferred compensation plan		18,859	17,856
Level 2
Fair Value, Balance Sheet Grouping [Line Items]
Derivative Asset	[1]	112,136	60,458
Assets held in trust for deferred compensation plan		0	0
Derivative Liabilities	[1]	58,674	54,865
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]	46	34
Assets held in trust for deferred compensation plan		0	0
Derivative Liabilities	[1]	44	119
Liabilities held in trust for deferred compensation plan		$ 0	$ 0

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