Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Cash and cash equivalents:
Cash and due from banks	$ 561,516	$ 476,653
Federal funds sold and interest-earning deposits with banks	4,099,342	6,018,915
Deposits in other financial institutions (restricted cash)	61,241	347,579
Total cash and cash equivalents	4,722,099	6,843,147
Trading securities, at fair value	88,088	77,689
Investment securities:
Securities held to maturity (fair value of $2,492,686 and $1,778,064)	2,806,465	1,819,901
Securities available for sale, at fair value	5,666,008	5,193,478
Other investments	179,815	160,568
Total investment securities	8,652,288	7,173,947
Loans held for sale	73,880	191,723
Loans:
Total loans	27,935,266	23,928,166
Less allowance for credit losses	(319,708)	(301,807)
Loans, net	27,615,558	23,626,359
Other real estate owned	1,431	2,736
Bank property held for sale	5,692	9,578
Premises and equipment, net	562,781	558,499
Bank owned life insurance ("BOLI")	953,970	783,049
Deferred tax assets	157,944	64,964
Derivatives assets	668,324	414,742
Mortgage servicing rights	87,463	65,620
Core deposit and other intangibles	132,694	128,067
Goodwill	1,922,525	1,581,085
Other assets	562,685	438,827
Total assets	46,207,422	41,960,032
Deposits:
Noninterest-bearing	14,337,018	11,498,840
Interest-bearing	24,538,833	23,555,989
Total deposits	38,875,851	35,054,829
Federal funds purchased	284,640	381,195
Securities sold under agreements to repurchase	385,359	400,044
Corporate and subordinated debentures	392,460	327,066
Reserve for unfunded commitments	32,543	30,510
Derivative liabilities	666,802	410,137
Other liabilities	529,342	553,311
Total liabilities	41,166,997	37,157,092
Shareholders' equity:
Common stock - $2.50 par value; authorized 160,000,000 shares; 75,641,322 and 69,332,297 shares issued and outstanding, respectively	189,103	173,331
Surplus	4,195,976	3,653,098
Retained earnings	1,146,230	997,657
Accumulated other comprehensive loss	(490,884)	(21,146)
Total shareholders' equity	5,040,425	4,802,940
Total liabilities and shareholders' equity	46,207,422	41,960,032
Acquired - non-purchased credit deteriorated loans
Loans:
Total loans	6,908,234	5,890,069
Acquired - purchased credit deteriorated loans
Loans:
Total loans	1,707,592	1,987,322
Non-acquired loans
Loans:
Total loans	$ 19,319,440	$ 16,050,775