Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Assets
Cash and due from banks	$ 332.9	$ 349.2
Interest bearing deposits in banks	747.7	521.2
Federal funds sold	0.1	0.1
Total cash and cash equivalents	1,080.7	870.5
Investment securities:
Available-for-sale, net of allowance for credit losses of $2.6 at March 31, 2023 and $0.0 at December 31, 2022 (amortized cost of $6,582.2 at March 31, 2023 and $7,573.5 at December 31, 2022)	6,049.3	6,946.1
Held-to-maturity, net of allowance for credit losses of $0.7 at March 31, 2023 and $1.9 at December 31, 2022 (estimated fair values of $3,025.8 at March 31, 2023 and $3,052.2 at December 31, 2022)	3,376.2	3,451.8
Total investment securities	9,425.5	10,397.9
Federal Home Loan Bank Stock and Federal Reserve Bank Stock	214.5	198.6
Loans held for sale	80.9	79.9
Loans held for investment, net of deferred fees and costs	18,245.7	18,099.2
Allowance for credit losses	226.1	220.1
Net loans held for investment	18,019.6	17,879.1
Goodwill	1,100.9	1,100.9
Bank Owned Life Insurance	499.4	497.9
Premises and equipment, net of accumulated depreciation	443.4	444.7
Other intangibles, net of accumulated amortization	93.0	97.0
Accrued interest receivable	113.7	118.3
Mortgage servicing rights, net of accumulated amortization and impairment reserve	30.1	31.1
Real Estate Acquired Through Foreclosure	13.4	12.7
Deferred tax assets	173.2	210.5
Other assets	349.4	348.7
Total assets	31,637.7	32,287.8
Deposits:
Non-interest bearing	6,861.1	7,560.0
Interest bearing	17,245.9	17,513.6
Total deposits	24,107.0	25,073.6
Securities sold under repurchase agreements	970.8	1,052.9
Accounts payable and accrued expenses	361.8	445.9
Accrued interest payable	26.1	14.5
Long-term debt	120.8	120.8
Other Short-term Borrowings	2,710.0	2,327.0
Allowance for credit losses on off-balance sheet credit exposures	17.8	16.2
Subordinated debentures held by subsidiary trusts	163.1	163.1
Total liabilities	28,477.4	29,214.0
Stockholders’ equity:
Preferred stock, no par value; 100,000 shares authorized; none issued and outstanding	0.0	0.0
Common stock, no par value; 150,000,000 shares authorized at March 31, 2023 and December 31, 2022; 104,382,018 and 104,442,023 shares were issued and outstanding, respectively	2,478.7	2,478.2
Retained earnings	1,080.7	1,072.7
Accumulated other comprehensive loss, net	(399.1)	(477.1)
Total stockholders’ equity	3,160.3	3,073.8
Total liabilities and stockholders’ equity	$ 31,637.7	$ 32,287.8
Common Stock, Shares Authorized	150,000,000	150,000,000