Fair Value Of Financial Instruments (Schedule Of Estimated Fair Value Of Financial Instruments) (Details) - USD ($) $ in Thousands		Mar. 31, 2023	Dec. 31, 2022
Carrying Amount
Fair Value, Balance Sheet Grouping [Line Items]
Loans		$ 16,535,522	$ 16,303,131
Loans held for sale		6,162	4,964
Investment securities		11,544,700	12,511,649
Federal Funds Sold		27,060	49,505
Securities purchased under agreements to resell		825,000	825,000
Interest earning deposits with banks		1,341,854	389,140
Cash and due from banks		351,210	452,496
Derivative Asset		100,157	60,492
Assets held in trust for deferred compensation plan		18,656	17,856
Assets, Fair Value Financial Instruments		30,750,321	30,614,233
Non-interest bearing deposits		8,685,234	10,066,356
Savings, interest checking and money market deposits		14,419,741	15,126,981
Certificates of deposits		1,578,485	994,103
Federal funds purchased		756,470	159,860
Securities sold under agreements to repurchase		2,028,089	2,681,874
Other borrowings		1,506,817	8,831
Derivative Liabilities		43,068	54,984
Liabilities held in trust for deferred compensation plan		18,656	17,856
Financial Liabilities Fair Value Disclosure		29,036,560	29,110,845
Carrying Amount | Business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		5,704,467	5,661,725
Carrying Amount | Real estate - construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		1,437,419	1,361,095
Carrying Amount | Real estate - business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,486,543	3,406,981
Carrying Amount | Real estate - personal
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,952,042	2,918,078
Carrying Amount | Consumer
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,094,389	2,059,088
Carrying Amount | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		295,478	297,207
Carrying Amount | Consumer credit card
Fair Value, Balance Sheet Grouping [Line Items]
Loans		558,669	584,000
Carrying Amount | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		6,515	14,957
Estimated Fair Value at March 31, 2023
Fair Value, Balance Sheet Grouping [Line Items]
Loans		15,937,550	15,645,261
Loans held for sale		6,162	4,964
Investment securities		11,544,700	12,511,649
Federal Funds Sold		27,060	49,505
Securities purchased under agreements to resell		804,959	795,574
Interest earning deposits with banks		1,341,854	389,140
Cash and due from banks		351,210	452,496
Derivative Asset		100,157	60,492
Assets held in trust for deferred compensation plan		18,656	17,856
Assets, Fair Value Financial Instruments		30,132,308	29,926,937
Non-interest bearing deposits		8,685,234	10,066,356
Savings, interest checking and money market deposits		14,419,741	15,126,981
Certificates of deposits		1,577,207	982,613
Federal funds purchased		756,470	159,860
Securities sold under agreements to repurchase		2,030,615	2,684,471
Other borrowings		1,506,817	8,831
Derivative Liabilities		43,068	54,984
Liabilities held in trust for deferred compensation plan		18,656	17,856
Financial Liabilities Fair Value Disclosure		29,037,808	29,101,952
Estimated Fair Value at March 31, 2023 | Business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		5,577,723	5,506,128
Estimated Fair Value at March 31, 2023 | Real estate - construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		1,407,614	1,347,328
Estimated Fair Value at March 31, 2023 | Real estate - business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,383,813	3,289,655
Estimated Fair Value at March 31, 2023 | Real estate - personal
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,700,721	2,654,423
Estimated Fair Value at March 31, 2023 | Consumer
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,033,884	1,999,788
Estimated Fair Value at March 31, 2023 | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		296,436	295,005
Estimated Fair Value at March 31, 2023 | Consumer credit card
Fair Value, Balance Sheet Grouping [Line Items]
Loans		530,987	538,268
Estimated Fair Value at March 31, 2023 | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		6,372	14,666
Estimated Fair Value at March 31, 2023 | Level 1
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Loans held for sale		0	0
Investment securities		1,026,806	1,041,616
Federal Funds Sold		27,060	49,505
Securities purchased under agreements to resell		0	0
Interest earning deposits with banks		1,341,854	389,140
Cash and due from banks		351,210	452,496
Derivative Asset		0	0
Assets held in trust for deferred compensation plan		18,656	17,856
Assets, Fair Value Financial Instruments		2,765,586	1,950,613
Non-interest bearing deposits		8,685,234	10,066,356
Savings, interest checking and money market deposits		14,419,741	15,126,981
Certificates of deposits		0	0
Federal funds purchased		756,470	159,860
Securities sold under agreements to repurchase		0	0
Other borrowings		2,930	0
Derivative Liabilities		0	0
Liabilities held in trust for deferred compensation plan		18,656	17,856
Financial Liabilities Fair Value Disclosure		23,883,031	25,371,053
Estimated Fair Value at March 31, 2023 | Level 1 | Business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 1 | Real estate - construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 1 | Real estate - business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 1 | Real estate - personal
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 1 | Consumer
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 1 | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 1 | Consumer credit card
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 1 | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 2
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Loans held for sale		6,162	4,964
Investment securities		10,248,563	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		100,036	60,458
Assets held in trust for deferred compensation plan		0	0
Assets, Fair Value Financial Instruments		10,354,761	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		3,887	8,831
Derivative Liabilities		42,920	54,865
Liabilities held in trust for deferred compensation plan		0	0
Financial Liabilities Fair Value Disclosure		46,807	63,696
Estimated Fair Value at March 31, 2023 | Level 2 | Business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 2 | Real estate - construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 2 | Real estate - business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 2 | Real estate - personal
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 2 | Consumer
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 2 | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 2 | Consumer credit card
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Level 2 | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		0	0
Estimated Fair Value at March 31, 2023 | Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping [Line Items]
Loans		15,937,550	15,645,261
Loans held for sale		0	0
Investment securities		269,331	225,441
Federal Funds Sold		0	0
Securities purchased under agreements to resell		804,959	795,574
Interest earning deposits with banks		0	0
Cash and due from banks		0	0
Derivative Asset		121	34
Assets held in trust for deferred compensation plan		0	0
Assets, Fair Value Financial Instruments		17,011,961	16,666,310
Non-interest bearing deposits		0	0
Savings, interest checking and money market deposits		0	0
Certificates of deposits		1,577,207	982,613
Federal funds purchased		0	0
Securities sold under agreements to repurchase		2,030,615	2,684,471
Other borrowings		1,500,000	0
Derivative Liabilities		148	119
Liabilities held in trust for deferred compensation plan		0	0
Financial Liabilities Fair Value Disclosure		5,107,970	3,667,203
Estimated Fair Value at March 31, 2023 | Significant Unobservable Inputs (Level 3) | Business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		5,577,723	5,506,128
Estimated Fair Value at March 31, 2023 | Significant Unobservable Inputs (Level 3) | Real estate - construction and land
Fair Value, Balance Sheet Grouping [Line Items]
Loans		1,407,614	1,347,328
Estimated Fair Value at March 31, 2023 | Significant Unobservable Inputs (Level 3) | Real estate - business
Fair Value, Balance Sheet Grouping [Line Items]
Loans		3,383,813	3,289,655
Estimated Fair Value at March 31, 2023 | Significant Unobservable Inputs (Level 3) | Real estate - personal
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,700,721	2,654,423
Estimated Fair Value at March 31, 2023 | Significant Unobservable Inputs (Level 3) | Consumer
Fair Value, Balance Sheet Grouping [Line Items]
Loans		2,033,884	1,999,788
Estimated Fair Value at March 31, 2023 | Significant Unobservable Inputs (Level 3) | Revolving home equity
Fair Value, Balance Sheet Grouping [Line Items]
Loans		296,436	295,005
Estimated Fair Value at March 31, 2023 | Significant Unobservable Inputs (Level 3) | Consumer credit card
Fair Value, Balance Sheet Grouping [Line Items]
Loans		530,987	538,268
Estimated Fair Value at March 31, 2023 | Significant Unobservable Inputs (Level 3) | Overdrafts
Fair Value, Balance Sheet Grouping [Line Items]
Loans		6,372	14,666
Interest earning deposits with banks		1,341,854	389,140
Cash and due from banks		351,210	452,496
Derivative Asset	[1]	100,157	60,492
Assets held in trust for deferred compensation plan		18,656	17,856
Non-interest bearing deposits		8,685,234	10,066,356
Savings, interest checking and money market deposits		14,419,741	15,126,981
Other borrowings		1,507,776	9,672
Derivative Liabilities	[1]	43,068	54,984
Liabilities held in trust for deferred compensation plan		18,656	17,856
Level 1
Fair Value, Balance Sheet Grouping [Line Items]
Derivative Asset	[1]	0	0
Assets held in trust for deferred compensation plan		18,656	17,856
Derivative Liabilities	[1]	0	0
Liabilities held in trust for deferred compensation plan		18,656	17,856
Level 2
Fair Value, Balance Sheet Grouping [Line Items]
Derivative Asset	[1]	100,036	60,458
Assets held in trust for deferred compensation plan		0	0
Derivative Liabilities	[1]	42,920	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]	121	34
Assets held in trust for deferred compensation plan		0	0
Derivative Liabilities	[1]	148	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.