Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Interest income:
Loans, including fees	$ 166,679	$ 182,695	$ 316,656	$ 350,178
Securities:
Taxable	56,365	20,602	99,423	40,630
Tax-exempt	57,078	56,111	113,944	112,774
Interest-bearing deposits	26,371	3,614	32,714	6,047
Federal funds sold	99	8	112	11
Resell agreements	10	4	14	5
Total interest income	306,602	263,034	562,863	509,645
Interest expense:
Deposits	14,593	3,499	19,505	7,016
Federal funds purchased	75	7	87	15
Repurchase agreements	1,790	570	2,308	965
Junior subordinated deferrable interest debentures	772	638	1,356	1,284
Subordinated notes	1,164	1,164	2,328	2,328
Total interest expense	18,394	5,878	25,584	11,608
Net interest income	288,208	257,156	537,279	498,037
Credit loss expense	0	0	0	63
Net interest income after credit loss expense	288,208	257,156	537,279	497,974
Non-interest income:
Trust and investment management fees	37,776	37,874	76,432	73,188
Service charges on deposit accounts	23,870	19,849	46,610	39,842
Insurance commissions and fees	11,776	10,773	28,384	28,086
Interchange and card transaction fees	4,911	4,641	9,137	8,734
Other charges, commissions and fees	9,887	8,640	19,514	16,944
Net gain (loss) on securities transactions	0	0	0	0
Other	9,707	9,470	19,240	17,689
Total non-interest income	97,927	91,247	199,317	184,483
Non-interest expense:
Salaries and wages	116,881	97,035	228,210	190,493
Employee benefits	20,733	18,728	44,953	41,264
Net occupancy	28,379	26,650	55,790	52,701
Technology, furniture and equipment	29,921	27,998	59,078	56,014
Deposit insurance	3,724	2,877	7,357	5,805
Intangible amortization	131	185	277	387
Other	46,578	41,781	89,414	78,732
Total non-interest expense	246,347	215,254	485,079	425,396
Income before income taxes	139,788	133,149	251,517	257,061
Income taxes	20,674	15,081	33,301	22,978
Net income	119,114	118,068	218,216	234,083
Preferred stock dividends	1,669	1,669	3,338	3,820
Net income available to common shareholders	$ 117,445	$ 116,399	$ 214,878	$ 230,263
Earnings per common share:
Basic	$ 1.82	$ 1.81	$ 3.32	$ 3.59
Diluted	$ 1.81	$ 1.80	$ 3.31	$ 3.57