Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Interest and Dividend Income, Operating [Abstract]
Interest and Fee Income, Loans and Leases	$ 426,989	$ 433,299
Interest and Dividend Income, Securities, by Taxable Status [Abstract]
Interest Income, Securities, Operating, Taxable	75,676	69,788
Interest Income, Securities, Operating, Tax Exempt	13,738	13,956
Other Interest and Dividend Income	11,641	9,243
Interest and Dividend Income, Operating, Total	528,044	526,285
Interest Expense, Operating and Nonoperating [Abstract]
Interest Expense, Deposits	175,273	209,140
Interest Expense, Federal Funds Purchased and Securities Sold under Agreements to Repurchase	3,732	3,622
Interest Expense, Other Short-Term Borrowings	116	408
Interest on FHLB Funding	31,570	16,090
Interest Expense, Long-Term Debt	10,163	11,085
Interest Expense, Operating and Nonoperating, Total	220,854	240,345
Interest Income (Expense), Operating, Total	307,190	285,941
Provision for Loan, Lease, and Other Losses	11,001	13,003
Interest Income (Expense), after Provision for Loan Loss, Total	296,189	272,938
Noninterest Income [Abstract]
Capital Market Fees Net	6,543	4,345
Fees and Commissions, Mortgage Banking and Servicing	6,111	3,822
Gain (Loss) on Sale of Mortgage Loans	0	(6,976)
Bank Owned Life Insurance Income	3,816	5,204
Gain (Loss) on Disposition of Assets	840	(878)
Debt Securities, Available-for-Sale, Realized Gain (Loss), Excluding Other-than-temporary Impairment	(28)	4
Noninterest Income, Other Operating Income	2,861	2,251
Noninterest Income, Total	75,857	58,776
Noninterest Expense [Abstract]
Labor and Related Expense	135,172	123,897
Information Technology and Data Processing	29,736	27,139
Occupancy, Net	13,725	15,381
Marketing and Advertising Expense	7,827	6,386
Equipment Expense	5,610	4,527
Professional Fees	6,721	6,083
Payments of Financing Costs	1,707	2,594
Federal Deposit Insurance Corporation Premium Expense	8,837	10,436
Amortization of Intangible Assets	2,203	2,203
Other Noninterest Expense	7,625	11,974
Noninterest Expense, Total	219,163	210,619
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest, Total	152,883	121,095
Income Tax Expense (Benefit)	33,248	19,409
Net Income (Loss) Attributable to Parent, Total	119,635	101,687
Preferred Stock Dividends and Other Adjustments	2,875	2,875
Net Income (Loss) Available to Common Stockholders, Basic, Total	$ 116,760	$ 98,812
Earnings Per Share [Abstract]
Earnings Per Share, Basic	$ 0.70	$ 0.60
Earnings Per Share, Diluted	$ 0.70	$ 0.59
Weighted Average Number of Shares Outstanding, Diluted [Abstract]
Weighted Average Number of Shares Outstanding, Basic	165,097	165,228
Weighted Average Number of Shares Outstanding, Diluted	166,561	166,604
Fiduciary and Trust [Member]
Noninterest Income [Abstract]
Noninterest Income In Scope of Topic 606	$ 25,219	$ 22,498
Deposit Account [Member]
Noninterest Income [Abstract]
Noninterest Income In Scope of Topic 606	14,054	12,814
Credit and Debit Card [Member]
Noninterest Income [Abstract]
Revenue from Contract with Customer, Including Assessed Tax, Out of Scope Topic 606	11,579	10,442
Financial Service, Other [Member]
Noninterest Income [Abstract]
Revenue from Contract with Customer, Including Assessed Tax, Out of Scope Topic 606	$ 4,862	$ 5,251