Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Interest income:
Loans, including fees	$ 149,977	$ 167,483
Securities:
Taxable	43,058	20,028
Tax-exempt	56,866	56,663
Interest-bearing deposits	6,343	2,433
Federal funds sold	13	3
Resell agreements	4	1
Total interest income	256,261	246,611
Interest expense:
Deposits	4,912	3,517
Federal funds purchased	12	8
Repurchase agreements	518	395
Junior subordinated deferrable interest debentures	584	646
Subordinated notes	1,164	1,164
Total interest expense	7,190	5,730
Net interest income	249,071	240,881
Credit loss expense	0	63
Net interest income after credit loss expense	249,071	240,818
Non-interest income:
Trust and investment management fees	38,656	35,314
Service charges on deposit accounts	22,740	19,993
Insurance commissions and fees	16,608	17,313
Interchange and card transaction fees	4,226	4,093
Other charges, commissions and fees	9,627	8,304
Net gain (loss) on securities transactions	0	0
Other	9,533	8,219
Total non-interest income	101,390	93,236
Non-interest expense:
Salaries and wages	111,329	93,458
Employee benefits	24,220	22,536
Net occupancy	27,411	26,051
Technology, furniture and equipment	29,157	28,016
Deposit insurance	3,633	2,928
Intangible amortization	146	202
Other	42,836	36,951
Total non-interest expense	238,732	210,142
Income before income taxes	111,729	123,912
Income taxes	12,627	7,897
Net income	99,102	116,015
Preferred stock dividends	1,669	2,151
Net income available to common shareholders	$ 97,433	$ 113,864
Earnings per common share:
Basic	$ 1.51	$ 1.78
Diluted	$ 1.50	$ 1.77