Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Interest income:
Interest and fees on loans	$ 252.1	$ 235.6
Interest and dividends on investment securities:
Taxable	64.5	72.2
Exempt from federal taxes	0.7	0.9
Other Interest and Dividend Income	3.3	3.0
Interest on deposits in banks	4.1	4.2
Total interest income	324.7	315.9
Interest expense:
Interest on deposits	79.1	40.3
Interest on securities sold under repurchase agreements	2.3	1.1
Interest Expense, Other Short-term Borrowings	35.6	31.2
Interest on long-term debt	4.3	1.5
Interest on subordinated debentures held by subsidiary trusts	3.3	2.9
Total interest expense	124.6	77.0
Net interest income	200.1	238.9
Provision for credit losses	5.3	15.2
Net interest income after provision for credit losses	194.8	223.7
Non-interest income:
Payment Services Revenues	18.4	18.7
Mortgage banking revenues	1.7	2.3
Wealth management revenues	9.2	9.0
Service Charges on Deposit Accounts	6.0	5.2
Non-interest income	2.2	2.4
Debt Securities, Available-for-sale, Gain (Loss)	0.0	(23.4)
Other income	4.6	2.2
Total non-interest income	42.1	16.4
Non-interest expense:
Salaries and wages	65.2	65.6
Employee benefits	19.3	22.8
Outsourced technology services	13.6	14.7
Occupancy, net	12.3	12.5
Furniture and equipment	5.0	5.9
OREO expense, net of income	2.0	0.2
Professional fees	6.8	4.5
FDIC insurance premiums	7.4	5.7
Other intangibles amortization	3.7	4.0
Other expenses	24.9	29.9
Noninterest Expense	160.2	165.8
Income before income tax	76.7	74.3
Provision for income tax	18.3	18.0
Net income	$ 58.4	$ 56.3
Earnings per common share, basic (in dollars per share)	$ 0.57	$ 0.54
Earnings per common share, diluted (in dollars per share)	$ 0.57	$ 0.54
Weighted average common shares outstanding, basic (in shares)	102,844,397	103,737,664
Weighted average common shares outstanding, diluted (in shares)	103,040,034	103,818,719