Revenue from Contracts with Customers (Schedule of Disaggregation of Revenue) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Disaggregation of Revenue [Line Items]
Non-interest income		$ 161,511	$ 159,025	$ 486,073	$ 460,117
Total non-interest income from contracts with customers
Disaggregation of Revenue [Line Items]
Non-interest income		148,747	146,754	449,111	425,760
Total non-interest income from contracts with customers | Trust fees
Disaggregation of Revenue [Line Items]
Non-interest income		58,412	54,689	170,575	158,085
Total non-interest income from contracts with customers | Bank card transaction fees
Disaggregation of Revenue [Line Items]
Non-interest income		45,551	47,570	137,506	141,977
Total non-interest income from contracts with customers | Deposit account charges and other fees
Disaggregation of Revenue [Line Items]
Non-interest income		27,427	25,380	80,297	74,856
Total non-interest income from contracts with customers | Consumer brokerage services
Disaggregation of Revenue [Line Items]
Non-interest income		6,698	4,619	16,866	13,505
Total non-interest income from contracts with customers | Other non-interest income
Disaggregation of Revenue [Line Items]
Non-interest income		10,659	14,496	43,867	37,337
Other non-interest income (1)
Disaggregation of Revenue [Line Items]
Non-interest income	[1]	$ 12,764	$ 12,271	$ 36,962	$ 34,357

[1] This revenue is not within the scope of ASC 606, and includes fees relating to bond trading activities, loan fees and sales, derivative instruments, standby letters of credit and various other transactions.