Revenue from Contracts with Customers (Schedule of Disaggregation of Revenue) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Disaggregation of Revenue [Line Items]
Non-interest income		$ 138,514	$ 137,506	$ 409,710	$ 412,694
Total non-interest income from contracts with customers
Disaggregation of Revenue [Line Items]
Non-interest income		130,010	124,336	383,161	364,828
Total non-interest income from contracts with customers | Bank card transaction fees
Disaggregation of Revenue [Line Items]
Non-interest income		45,638	42,815	131,556	123,118
Total non-interest income from contracts with customers | Trust fees
Disaggregation of Revenue [Line Items]
Non-interest income		45,406	48,950	140,009	139,334
Total non-interest income from contracts with customers | Deposit account charges and other fees
Disaggregation of Revenue [Line Items]
Non-interest income		24,521	25,161	72,392	71,724
Total non-interest income from contracts with customers | Consumer brokerage services
Disaggregation of Revenue [Line Items]
Non-interest income		5,085	4,900	14,599	13,484
Total non-interest income from contracts with customers | Other non-interest income
Disaggregation of Revenue [Line Items]
Non-interest income		9,360	2,510	24,605	17,168
Other non-interest income (1)
Disaggregation of Revenue [Line Items]
Non-interest income	[1]	$ 8,504	$ 13,170	$ 26,549	$ 47,866

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