Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Assets
Cash and due from banks	$ 315.8	$ 378.2
Interest bearing deposits in banks	319.1	199.7
Federal funds sold	0.1	0.1
Total cash and cash equivalents	635.0	578.0
Investment securities:
Available-for-sale, net of allowance for credit losses of $0.0 at March 31, 2024 and December 31, 2023 (amortized cost of $6,266.0 at March 31, 2024 and $6,307.8 at December 31, 2023)	5,773.3	5,841.5
Held-to-maturity, net of allowance for credit losses of $0.7 at March 31, 2024 and $0.8 at December 31, 2023 (estimated fair values of $2,497.8 at March 31, 2024 and $2,874.0 at December 31, 2023)	2,852.8	3,207.9
Total investment securities	8,626.1	9,049.4
Federal Home Loan Bank Stock and Federal Reserve Bank Stock	178.4	223.2
Loans held for sale	22.7	47.4
Loans held for investment, net of deferred fees and costs	18,202.8	18,279.6
Allowance for credit losses	(227.7)	(227.7)
Net loans held for investment	17,975.1	18,051.9
Goodwill	1,100.9	1,100.9
Bank Owned Life Insurance	504.7	502.4
Premises and equipment, net of accumulated depreciation	439.9	444.3
Other intangibles, net of accumulated amortization	77.7	81.4
Accrued interest receivable	125.5	129.1
Mortgage servicing rights, net of accumulated amortization	27.6	28.3
Real Estate Acquired Through Foreclosure	14.4	16.5
Deferred tax assets	161.3	150.0
Other assets	255.5	268.4
Total assets	30,144.8	30,671.2
Deposits:
Non-interest bearing	5,900.3	6,029.6
Interest bearing	16,909.7	17,293.5
Total deposits	22,810.0	23,323.1
Securities sold under repurchase agreements	794.2	782.7
Accounts payable and accrued expenses	386.0	380.4
Accrued interest payable	53.6	52.2
Long-term debt	370.8	120.8
Other Short-term Borrowings	2,342.0	2,603.0
Allowance for credit losses on off-balance sheet credit exposures	15.4	18.4
Subordinated debentures held by subsidiary trusts	163.1	163.1
Total liabilities	26,935.1	27,443.7
Stockholders’ equity:
Preferred stock, no par value; 100,000 shares authorized; none issued and outstanding	0.0	0.0
Common stock and additional paid-in-capital, $0.00001 par value; 150,000,000 shares authorized; 104,571,623 and 103,941,626 shares were issued and outstanding at March 31, 2024 and December 31, 2023	2,450.7	2,448.9
Retained earnings	1,145.9	1,135.1
Accumulated other comprehensive loss, net	(386.9)	(356.5)
Total stockholders’ equity	3,209.7	3,227.5
Total liabilities and stockholders’ equity	$ 30,144.8	$ 30,671.2
Common Stock, Shares Authorized	150,000,000