Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Cash and cash equivalents:
Cash and due from banks	$ 510,922	$ 548,387
Federal funds sold and interest-earning deposits with banks	236,435	580,491
Deposits in other financial institutions (restricted cash)	251,520	183,685
Total cash and cash equivalents	998,877	1,312,563
Trading securities, at fair value	31,321	31,263
Investment securities:
Securities held to maturity (fair value of $2,084,736 and $2,250,168)	2,487,440	2,683,241
Securities available for sale, at fair value	4,784,388	5,326,822
Other investments	192,043	179,717
Total investment securities	7,463,871	8,189,780
Loans held for sale	50,888	28,968
Loans:
Total loans	32,388,489	30,177,862
Less allowance for credit losses	(456,573)	(356,444)
Loans, net	31,931,916	29,821,418
Other real estate owned	837	1,023
Bank property held for sale	12,401	17,754
Premises and equipment, net	519,197	520,635
Bank owned life insurance ("BOLI")	991,454	964,708
Deferred tax assets	164,354	177,801
Derivatives assets	172,939	211,016
Mortgage servicing rights	85,164	86,610
Core deposit and other intangibles	88,776	116,450
Goodwill	1,923,106	1,923,106
Other assets	466,923	515,601
Total assets	44,902,024	43,918,696
Deposits:
Noninterest-bearing	10,649,274	13,168,656
Interest-bearing	26,399,635	23,181,967
Total deposits	37,048,909	36,350,623
Federal funds purchased	248,162	213,597
Securities sold under agreements to repurchase	241,023	342,820
Corporate and subordinated debentures	391,904	392,275
Other borrowings	100,000
Reserve for unfunded commitments	56,303	67,215
Derivative liabilities	804,486	1,034,143
Other liabilities	478,139	443,096
Total liabilities	39,368,926	38,843,769
Shareholders' equity:
Common stock - $2.50 par value; authorized 160,000,000 shares; 76,022,039 and 75,704,563 shares issued and outstanding, respectively	190,055	189,261
Surplus	4,240,413	4,215,712
Retained earnings	1,685,166	1,347,042
Accumulated other comprehensive loss	(582,536)	(677,088)
Total shareholders' equity	5,533,098	5,074,927
Total liabilities and shareholders' equity	44,902,024	43,918,696
Acquired - non-purchased credit deteriorated loans
Loans:
Total loans	4,796,913	5,943,092
Acquired - purchased credit deteriorated loans
Loans:
Total loans	1,108,813	1,429,731
Non-acquired loans
Loans:
Total loans	$ 26,482,763	$ 22,805,039