Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Assets
AFS investment securities, at fair value	$ 3,491,679	$ 2,742,025
HTM investment securities, net, at amortized cost	3,900,415	3,960,398
Equity Securities, FV-NI and without Readily Determinable Fair Value	35,937	25,216
FHLB and Federal Reserve Bank stocks, at cost	268,698	295,496
Residential loans held for sale	54,790	20,383
Loans	30,193,187	28,799,569
Allowance for loan losses	(345,795)	(312,720)
Tax credit and other investments	256,905	276,773
Premises and equipment, net	373,017	376,906
Goodwill	1,104,992	1,104,992
Other intangible assets, net	42,674	49,282
Mortgage servicing rights, net	89,131	77,351
Interest receivable	171,119	144,449
Other assets	608,068	547,621
Total assets	41,637,381	39,405,727
Liabilities and stockholders' equity
Noninterest-bearing demand deposits	6,422,994	7,760,811
Interest-bearing deposits	25,700,332	21,875,343
Total deposits	32,123,326	29,636,154
Federal funds purchased and securities sold under agreements to repurchase	451,644	585,139
Commercial paper	0	20,798
FHLB advances	3,733,041	4,319,861
Allowance for unfunded commitments	34,776	38,776
Accrued expenses and other liabilities	637,491	541,438
Total liabilities	37,509,738	35,390,237
Stockholders’ equity
Preferred equity	194,112	194,112
Common stock	1,752	1,752
Surplus	1,711,454	1,712,733
Retained earnings	3,074,014	2,904,882
Accumulated other comprehensive (loss)	(339,140)	(272,799)
Treasury stock, at cost	(514,549)	(525,190)
Total common equity	3,933,531	3,821,378
Total stockholders’ equity	4,127,643	4,015,490
Total liabilities and stockholders’ equity	$ 41,637,381	$ 39,405,727
Preferred shares authorized (par value $1.00 per share)	750,000	750,000
Preferred shares issued and outstanding	200,000	200,000
Common shares authorized (par value $0.01 per share)	250,000,000	250,000,000
Common shares issued	175,216,409	175,216,409
Common shares outstanding	150,951,209	150,444,019
Preferred shares, par value	$ 1.00	$ 1.00
Common shares, par value	$ 0.01	$ 0.01
Fair Value, Inputs, Level 2
Assets
AFS investment securities, at fair value	$ 3,382,655	$ 2,632,647
Bank and corporate owned life insurance	679,775	676,530
Liabilities and stockholders' equity
FHLB advances	3,733,041	4,319,861
Other long-term funding	529,459	248,071
Fair Value, Inputs, Level 3
Assets
Equity Securities, FV-NI and without Readily Determinable Fair Value	19,236	19,225
Loans, net	29,847,392	28,486,849
Mortgage servicing rights, net	89,131	77,351
Fair Value, Inputs, Level 1
Assets
Cash and due from banks	388,694	436,952
Interest-bearing deposits in other financial institutions	323,130	156,693
Federal funds sold and securities purchased under agreements to resell	965	27,810
AFS investment securities, at fair value	$ 109,024	$ 109,378